TY - CONF A1 - Maiwald, Michael T1 - Sensors, Analytics and Certified Reference Materials safeguarding the quality infrastructure in the hydrogen economy N2 - The prerequisites for a successful energy transition and the economic use of hydrogen as a clean green energy carrier and for H2 readiness are a rapid market ramp-up and the establishment of the required value chains. Reliable quality and safety standards for innovative technologies are the prerequisite for ensuring supply security, for environmental compatibility and sustainable climate protection, for building trust in these technologies and thus enable product and process innovations. With the Competence Centre "H2Safety@BAM", BAM is creating the safety-related prere-quisites for the successful implementation of hydrogen technologies at national as well as European level. BAM uses decades of experience in dealing with hydrogen technologies to develop the necessary quality and safety standards. The presentation will draw a bow from the typical basic tasks of BAM in the field of competence "Sensors, analytics and certified reference materials", such as maintenance and dissemination of the national gas composition standards for calorific value determination as Designated Institute for Metrology in Chemistry within the framework of the Metre Convention, to the further development of measurement and sensor technology for these tasks. For the certification of reference materials, a mostly slow and time-consuming but solid reference analysis is common. With hydrogen and its special properties, completely new requirements are added. In addition, fast and simple online analysis is required for process control, for example to register quality changes, e.g., during load changes or refuelling processes. T2 - Indo-German International Conference on Metrology for the Deployment of Green Hydrogen and Renewable Fuels in India CY - Online meeting DA - 04.04.2022 KW - Quality Infrastructure KW - Gas Reference Material KW - Hydrogen KW - Energy Gases KW - Sensors KW - Hydrogen Storage Materials PY - 2022 UR - https://www.imeko-gh2fuels.ptb.de/ AN - OPUS4-54596 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maiwald, Michael T1 - Competence Centre H2Safety@BAM – Safeguarding the Quality Infrastructure in the Hydrogen Economy N2 - Hydrogen is a central component of the energy transition and the European Green Deal for a climate-neutral Europe. To achieve the goals defined for 2050, the EU and the German government have developed a framework for action and are making long-term investments in research, development, and the rapid implementation of innovative hydrogen technologies. With the Competence Centre "H2Safety@BAM", BAM is creating the safety-related prerequisites for the successful implementation of hydrogen technologies at national as well as European level. To this end, BAM conducts research, testing and consulting in a holistic and inter-disciplinary manner under one roof – in the Competence Centre H2Safety@BAM. The activities of the competence centre focus on ensuring the safety of infra-structures, plants, and processes as well as innovative hydrogen transport and storage systems based on digital quality testing and the experimental testing of components and systems. It thus creates the prerequisites for the implementation and adaptation of legal framework conditions as well as for standardization. Closely related to this are investigations into the properties and compatibility of metallic materials and polymers as well as friction systems for the safe operation of components, plants, processes, and systems. This interdisciplinary and holistic approach is complemented by the development of gas analytics and suitable sensors, online measurements of gas properties in process control, test scenarios under real conditions as well as impact assessments of accidents and risk assessments and risk management systems derived from them. With its portfolio of tasks and competences, BAM builds trust in the safety and reliability of technical system solutions for hydrogen. T2 - 772. WE-Heraeus-Seminar - Metrology and Process Safety for Hydrogen Technologies & Applications CY - Bad Honnef, Germany DA - 10.10.2022 KW - H2Safety@BAM KW - Hydrogen KW - Competence Center KW - Hydrogen Strategy KW - Green Deal KW - Safety KW - Risk Assessment KW - Quality Infrastructure PY - 2022 UR - https://www.we-heraeus-stiftung.de/veranstaltungen/metrology-and-process-safety-for-hydrogen-technologies-and-applications/ AN - OPUS4-55986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mayr, P. T1 - Hydrogen diffusion in creep-resistant 9%-Cr steel welds N2 - 9 %-Cr steels like P91 and P92 are widely used in power plants due to the excellent creep-resistance. Components of this steel are typically welded and demand for careful welding fabrication, whereas a so-called post weld heat treatment (PWHT), must be conducted to increase the toughness and decrease the hardness of the martensitic as-welded (AW) microstructure. Before the PWHT, a hydrogen removal (or dehydrogenation) heat treatment is necessary as hardened AW martensitic microstructure is generally prone to delayed hydrogen assisted cracking (HAC). The microstructure and temperature dependent hydrogen diffusion is an important issue as it determines how long a potential crack-critical hydrogen concentration could remain in the microstructure. In this context, reliable hydrogen diffusion coefficients of P91 and P92 weld metal are rare. T2 - IIW Intermediate Meeting, Commission IX-C "Creep and heat resistant welds" CY - Miami, FL, USA DA - 12.03.2019 KW - Hydrogen KW - Diffusion KW - Weld metal KW - Creep-resistant steel PY - 2019 AN - OPUS4-48450 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naster, Maximilian T1 - Experimental and Numerical Analyses for the Evaluation of Hydrogen as an Energy Source for Thermal Testing of Transport Packages of Radioactive Material N2 - In this paper we present a new hydrogen-based test rig for an ongoing feasibility study of using hydrogen as an energy source for the thermal testing of transport packages containing radioactive materials. The test rig will be capable of combusting hydrogen for a wide range of different burner geometries, mass flows and if necessary hydrogen blends. As this type of fire test according to the IAEA boundary conditions does not yet exist, a large number of preliminary investigations, safety assessments and calculations must be carried out in order to develop a viable concept for hydrogen fires. In the first step of the feasibility study, the temperature, structure, and radiation of various hydrogen flames are surveyed. In future works, the results will make it possible to design burner frames that are suitable for fire reference tests in order to make comparisons with pool and propane fires used in assessment procedures today. In parallel comparative numerical simulations are conducted to model the thermal behaviour of hydrogen flames using the software package Ansys®. On the one hand, the numerical simulations support the experiments by providing an overview of numerous parameters and the measuring range; on the other hand, they will help with the design of the burner frame in future work. This paper gives an overview in the design and capabilities of the test rig. Furthermore, the results of the parameter studies show that burner geometry and mass flow provide a significant design margin for the thermal shape of the hydrogen flames. In addition, the results of the initial numerical calculations will be used to determine the necessary sensors, the positions, and their operating range. Only the optimal interaction allows a controlled system that permits user-defined hydrogen fires. T2 - PVP2024, Pressure Vessels & Piping Conference CY - Bellevue, Washington, USA DA - 29.07.2024 KW - Hydrogen KW - Fire KW - IAEA Regulations KW - CFD KW - Burner PY - 2024 AN - OPUS4-60855 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naster, Maximilian T1 - Hydrogen Fire Testing N2 - In this presentation we present a new hydrogen-based test rig for an ongoing feasibility study of using hydrogen as an energy source for the thermal testing of transport packages containing radioactive materials. The test rig will be capable of combusting hydrogen for a wide range of different burner geometries, mass flows and if necessary hydrogen blends. As this type of fire test according to the IAEA boundary conditions does not yet exist, a large number of preliminary investigations, safety assessments and calculations must be carried out in order to develop a viable concept for hydrogen fires. In the first step of the feasibility study, the temperature, structure, and radiation of various hydrogen flames are surveyed. In future works, the results will make it possible to design burner frames that are suitable for fire reference tests in order to make comparisons with pool and propane fires used in assessment procedures today. In parallel comparative numerical simulations are conducted to model the thermal behaviour of hydrogen flames using the software package Ansys®. On the one hand, the numerical simulations support the experiments by providing an overview of numerous parameters and the measuring range; on the other hand, they will help with the design of the burner frame in future work. This paper gives an overview in the design and capabilities of the test rig. Furthermore, the results of the parameter studies show that burner geometry and mass flow provide a significant design margin for the thermal shape of the hydrogen flames. In addition, the results of the initial numerical calculations will be used to determine the necessary sensors, the positions, and their operating range. Only the optimal interaction allows a controlled system that permits user-defined hydrogen fires. T2 - Technical Exchange IRSN – BAM Transport & Storage of Packages for Radioactive Material CY - Berlin, Germany DA - 04.06.2024 KW - Hydrogen PY - 2024 AN - OPUS4-60341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naster, Maximilian T1 - Experimental and numerical analyses of hydrogen flames for the thermal testing of transport packages for radioactive material N2 - In this paper we present an update of the hydrogen-based test rig for an ongoing feasibility study of using hydrogen as an energy source for the thermal testing of transport packages containing radioactive materials. The test rig is capable of combusting hydrogen for a wide range of different burner geometries, mass flows, hydrogen blends and single jet flame operations as well as a full array of burners for thermal testing can be set up. As this type of fire test according to the IAEA boundary conditions does not yet exist, a large number of preliminary investigations, safety assessments and simulations must be carried out in order to develop a viable concept for hydrogen fires. In a first step of the feasibility study, the temperature, structure, and radiative behavior of hydrogen jet flames must be surveyed. The simulation with a single hydrogen flame was investigated in a previous work. In the next step the results are used to study the interaction and structural behavior of multiple jet flames in proximity with varying nozzle distances. With the test rig completed, it will be possible in future works to design burner frames suitable for fire reference tests to make comparisons with pool and propane fires used in assessment procedure today. Thus, preliminary comparative numerical simulations are conducted to model the behavior of overlapping hydrogen jet flames using the software package Ansys®. This paper gives an overview on the current state and design of the test rig. Furthermore, the results of the simulations show that nozzle geometry, mass flow and nozzle distance provide significant design margin for designing a test fire capable of fully engulfing a specimen. T2 - PVP2025, Pressure Vessels & Piping Conference CY - Montreal, Quebec, Canada DA - 20.07.2025 KW - Computational Fluid Dynamics (CFD) KW - Hydrogen KW - IAEA fire test PY - 2025 AN - OPUS4-63865 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nguyen, Ngoc Tam Thi T1 - Reinventing Piping for Hydrogen Applications – A Composite Approach N2 - A key step towards achieving climate neutrality in the European Union (EU) by 2050 is the transition to renewable energy sources. Green hydrogen plays a central role in this shift but remains costly, particularly through the utilization of PEM electrolysis. Currently, around 50% of the costs associated with electrolyser systems are attributed to system peripherals, underscoring the potential for cost savings through standardization and the use of cost-effective materials [Tja17, IRE20]. In the collaborative project "PolyH2Pipe", the Institute of Plastics Processing in Industry and Craft (IKV), the Welding and Joining Institute (ISF) and BAM Division 5.3 are developing media-carrying pipe systems made of continuous fiber-reinforced thermoplastics (TP-FR) for hydrogen applications. The project aims to design these pipes, develop suitable joining techniques and validate the requirements for these piping systems. This research initiative serves as a foundational basis for the subsequent market introduction of large-scale TP-FR pipe systems for electrolysers and fuel cell systems. Initial test results will be presented as a part of the talk during the colloquium. T2 - H2Safety Colloquium - Materials compatibility and properties CY - Online meeting DA - 14.05.2025 KW - Hydrogen KW - Polymer Matrix Composites KW - Electrolyser KW - Piping PY - 2025 AN - OPUS4-63134 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nietzke, Jonathan T1 - H2HohlZug: Standardisation of a New, Cost-effective Method for Material Characterisation for the Hydrogen Economy N2 - The feasibility of the method for slow strain tensile tests has been demonstrated in several studies, leading to the establishment of the ISO/TC 164/SC 1/WG 9 ISO committee for its standardisation. Questions have emerged during this process, that currently prevent the method from being standardised for hydrogen testing. These questions relate to specimen geometry, specimen manufacturing and gas quality and are being systematically addressed in the TransHyDE-H2HohlZug project. T2 - TrasnsHyDE Abschlusskonferenz CY - Berlin, Germany DA - 25.03.2025 KW - Hydrogen KW - Hydrogen Embrittlement KW - High-Pressure Gaseous Gas KW - Hollow Specimen Technique KW - TransHyDE KW - H2HohlZug PY - 2025 AN - OPUS4-62823 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nietzke, Jonathan T1 - Hydrogen diffusion and desorption characteristics of a CoCrFeMnNi high entropy and a CoCrNi medium entropy alloy N2 - Future structural components made of the novel high-entropy (HEA) or medium-entropy alloys (MEA) components can be potentially exposed to hydrogen containing environments like high-temperature water in pressurized nuclear reactors or aerospace structures. Further applications are vessels wall materials for cryogenic or high-pressure hydrogen storage. So far, the susceptibility of HEA/MEAs to hydrogen assisted cracking (if any) and the hydrogen diffusion is not investigated in detail yet and can limit or extend possible applications of HEA/MEA as structural materials. In our work, we focused on the hydrogen absorption, diffusion, and distribution in a HEA (Co20Cr20Fe20Mn20Ni20, the original Cantor-alloy) and a MEA (Co33.3Cr33.3Ni33.3). Conventional cathodic hydrogen charging was carried out for the hydrogen ingress in the materials. Thermal desorption analysis (TDA) via carrier gas hot extraction with coupled mass spectrometry revealed complex hydrogen trapping in both alloy types up to 300 °C. The absorbed total hydrogen concentrations were ≥ 70 ppm for the HEA and approximately 40 ppm for the MEA-type. Although both materials have different chemical composition, the TDA spectra were comparable. In addition, it was shown that the consideration of the sample geometry is an important influence on the sample temperature. It decreases the effective applied heating rate, which must be anticipated for each hydrogen peak after deconvolution of the spectra. This increases the activation energy and shifts the peak to lower temperatures. As a result, microstructure effects can be separated from experimental boundary conditions like the concentration gradient due to the charging process and later thermal activation. T2 - 4th International Conference on Metals and Hydrogen - Steely & Hydrogen 2022 CY - Ghent, Belgium DA - 11.10.2022 KW - High-entropy alloy KW - Diffusion KW - Hydrogen KW - Thermal desorption analysis KW - Trapping PY - 2022 AN - OPUS4-56007 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nietzke, Jonathan T1 - Evolution of tensile testing methodologies for hydrogen embrittlement in austenitic steels: a comparative study N2 - The energy transition towards hydrogen utilisation has increased the demand for reliable testing methods to evaluate the susceptibility of metallic materials to hydrogen degradation. However, traditional electrochemical pre-charging techniques have limitations in represent-ing realistic gaseous hydrogen exposure conditions. This study presents three comparative analyses of tensile testing methodologies, focusing on the differences between electrochem-ical pre-charging, gaseous pre-charging, and in-situ testing using hollow specimens for aus-tenitic steels AISI 304L and 316L type austenitic steels. Based on the results obtained, the first comparison reveals that electrochemically pre-charged and gaseously pre-charged specimens exhibit different behaviours regarding the impact on the mechanical properties. This effect can be retraced to the varying distribution of hydrogen throughout the specimens. Although comparable embrittlement was observed for similar hydrogen concentrations, the relationship appears to be non-systematic. The second comparison evaluates the performance of pre-charged hollow specimens (300°C, 100 bar, 21 days) in comparison to hollow specimens tested in-situ under 200 bar hydrogen during slow strain rate tensile tests (SSRT). While pre-charged specimens show a slight de-crease in elongation at fracture and a noticeable decrease in reduction of area (RA), in-situ tested specimens exhibit significantly more pronounced embrittlement. This is in accord-ance with the results of Michler et. al. In the third comparison, geometry effects between pre-charged conventional and pre-charged hollow specimens are explored. In this case, the hydrogen effect appears to be of the same order of magnitude for both specimen types, although some differences are ob-served. The study's findings underscore the importance of considering differences between test methods when assessing materials’ compatibility with hydrogen. It specifically emphasises the need for in-situ testing with gaseous hydrogen to better represent real conditions in ap-plications within the hydrogen sector. Furthermore, the study provides an initial compari-son between conventional and hollow specimens, demonstrating their capability to reveal hydrogen effects. However, additional research is essential to enhance the comparability of results yielded by these testing methods. T2 - European Conference on Fracture 2024 CY - Zagreb, Croatia DA - 26.08.2024 KW - Hollow Specimen Technique KW - Hydrogen KW - Austenitic Stainless Steel KW - Hydrogen Testing KW - AISI 316L PY - 2024 AN - OPUS4-60929 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nörthemann, K. T1 - Forest fire detection using hydrogen sensors N2 - Forest fires start mostly in partial combustion. In this paper we present a hydrogen sensor to detect early stages of forest fires. First indoor experiments in a smoke density chamber with wood samples, proved that the sensor produce a strong signal change when the smouldering of wood starts, already before the CO concentration, measured in FTIR spectrometry, exceeds 10 ppm. Indoor experiments in a Smoke Density Chamber with wood samples show, that our sensor produces an earlier signal difference than a carbon monoxide detector. In outdoor experiments we were able to detect forest fire in a distance of 110 m. T2 - AUBE 15- 15zh International conference on automatic fire detection CY - Duisburg, Germany DA - 14.10.2014 KW - Hydrogen KW - Fire KW - Early fire detection PY - 2014 AN - OPUS4-38285 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Orellana Pérez, Teresa T1 - European strategies, networks, projects, committees and initiatives & associations for promoting hydrogen safety and education N2 - This lecture shows an overview of cross-cutting topics whithin the dynamic sector of hydrogen technologies including European and other international strategies, legal and policy frameworks, networks and relevant stakeholders, research and demo-projects, regulations, codes & Standards as well as initiatives and associations concerning hydrogen safety and education. T2 - Joint European Summer School on Fuel Cell, Electrolyser and Battery Technologies JESS 2021 CY - Online meeting DA - 12.09.2021 KW - Hydrogen KW - Cross-cutting issues KW - Competence centre H2Safety@BAM PY - 2021 AN - OPUS4-54199 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Orellana Pérez, Teresa T1 - European policy framework regulations codes and standards for safe hydrogen technologies N2 - This lecture describes the history of hydrogen from the first scientific discoveries in the 18th century to the current technological and political developments for the market ramp-up of hydrogen technologies. The European policy framework for safe hydrogen technologies is explained comprehending the European Green Deal, European Climate Law, European Hydrogen Strategy, Clean Hydrogen Partnership, etc. Safety in hydrogen technologies is governed by international and European regulations and standards. An overview on regulatory bodies, technical committees, regulations, directives, standards, and technical guidelines with special attention on the BAM-GGR 021 is given in this lecture. T2 - Joint European Summer School 2022, Hydrogen Safety CY - Athens, Greece DA - 18.09.2022 KW - Hydrogen KW - Safety KW - Regulations KW - Standards PY - 2022 AN - OPUS4-59295 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Orellana Pérez, Teresa T1 - Guest lecture: European policy framework regulations codes and standards for safe hydrogen technologies N2 - This lecture describes the history of hydrogen from the first scientific discoveries in the 18th century to the current technological and political developments for the market ramp-up of hydrogen technologies. The European policy framework for safe hydrogen technologies is explained comprehending the European Green Deal, European Climate Law, European Hydrogen Strategy, Clean Hydrogen Partnership, etc. Safety in hydrogen technologies is governed by international and European regulations and standards. An overview on regulatory bodies, technical committees, regulations, directives, standards, and technical guidelines with special attention on the BAM-GGR 021 is given in this lecture. T2 - MSc Fuel Cells and Hydrogen Technologies at the University of Birmingham (LM Hydrogen Safety, MSc FCHT module C7B) CY - Birmingham, UK DA - 21.10.2022 KW - Hydrogen KW - Safety KW - Regulations KW - Standards PY - 2022 AN - OPUS4-59296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Orellana Pérez, Teresa T1 - European policy framework for safe hydrogen technologies N2 - This lecture describes the history of hydrogen from the first scientific discoveries in the 18th century to the current technological and political developments for the market ramp-up of hydrogen technologies. The European policy framework for safe hydrogen technologies is explained comprehending the European Green Deal, European Climate Law, European Hydrogen Strategy, Clean Hydrogen Partnership, REPowerEU Plan, Renewable Energy Directive and its Delegated Act, Net Zero Industry Act, etc. T2 - Joint European Summer School 2023, Hydrogen Safety CY - Athens, Greece DA - 17.09.2023 KW - Hydrogen KW - Safety KW - Policies PY - 2023 AN - OPUS4-59297 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Orellana Pérez, Teresa T1 - Regulations codes and standards for safe hydrogen technologies N2 - Safety in hydrogen technologies in Europe is governed by international and European regulations and standards. An overview on regulatory bodies, technical committees, regulations, directives, standards, and technical guidelines with special attention on the BAM-GGR 021 is given in this lecture. T2 - Joint European Summer School 2023, Hydrogen Safety CY - Athens, Greece DA - 17.09.2023 KW - Hydrogen KW - Safety KW - Regulations KW - Standards PY - 2023 AN - OPUS4-59300 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Popiela, Bartosz T1 - PhD Topic 5: Summer School Update. Influence of manufacturing process related residual stresses in wound composite material on the operational safety of H2 pressure vessels N2 - The presentation is an update on the progress of the PhD Project. It focuses on the residual stress induction during the winding process of type 4 composite pressure vessels. Moreover, an overview of the experimental study is given, with focus on the manufacturing of composite pressure vessels. T2 - Summer School 2023 - BTU-BAM Graduate School "Trustworthy Hydrogen" CY - Berlin, Germany DA - 04.09.2023 KW - Residual stress KW - Composite KW - Pressure vessel KW - Hydrogen PY - 2023 AN - OPUS4-58239 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Popiela, Bartosz T1 - Influence of manufacturing process related residual stresses in wound composite material on the operational safety of H2 pressure vessels: PhD Topic Introduction N2 - Short introduction of the PhD Topic 5 in the BTU-BAM Graduate School "Trustworthy Hydrogen". Description of the objectives, deliverables and expected added value of the thesis. T2 - Introduction Week - BTU-BAM Graduate School "Trustworthy Hydrogen" CY - Berlin, Germany DA - 16.01.2023 KW - Residual stress KW - Composite KW - Pressure vessel KW - Hydrogen PY - 2023 AN - OPUS4-56882 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Recknagel, Sebastian T1 - Non-metals in inorganic reference materials N2 - The analysis of non-metals normally is carried out using elemental analysers which require reference material for calibration. In the lecture the CRM-program of BAM suitable for non-metal-analysis is presented. There are CRMs available with non-metal contents in the low ppm up to the high percent region. T2 - CETAMA 2018 CY - Paris, France DA - 27.11.2018 KW - CRM KW - Non-metals KW - Carbon KW - Sulfur KW - Oxygen KW - Nitrogen KW - Hydrogen KW - Reference material PY - 2018 AN - OPUS4-46968 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Repair welding of pressurized in-service hydrogen pipelines - A review on current challenges and strategies N2 - As energy carrier of the future, green hydrogen can make a decisive contribution to a sustainable energy supply. Particularly important is the decarbonization of heavy industry. Therefore, a reliable supply of hydrogen must be guaranteed. A hydrogen pipeline grid can achieve this purpose. In Europe concrete plans for a hydrogen pipeline grid already exist, as the so called “European Hydrogen backbone”. As building a completely new pipeline grid is economically not justifiable, a dual-way strategy of repurposing natural gas (NG) pipelines and newly built pipelines is intended. Long distance pipeline grids require regular maintenance and repairs. For natural gas (NG) pipelines in-service welding is state of the art. Concepts such as hot-tapping (drilling into pressurized pipelines) and “stoppling” (sealing off pipeline sections after installing bypasses or pressure relieves) allow the repair of damaged pipeline sections or the installation of new branches without shutting the pipeline down, which in most cases isn’t possible from an economic standpoint. The EIGA 121/14 guideline already pointed out in 2014 that “a hydrogen hot-tap shall not be considered a routine procedure”. This shows that the determination of the transferability of these repair concepts to hydrogen pipelines is of utmost importance. Due to the degrading effects of hydrogen on mechanical proper-ties, commonly referred to as “hydrogen embrittlement” it is necessary to understand and investigate the occurring effects. In the special case of repair welding on in-service hydrogen pipelines an increased hydro-gen uptake due to a large heat input and microstructural changes in the material needs to be considered. Therefore, material degradation must be investigated to determine whether modifications of repair procedures are necessary to ensure a reliable and safe hydrogen transportation via pipelines. For this reason, this paper gives an overview on existing weld repair concepts and its risks and limitations in terms of hydrogen absorption and possible embrittlement effects when transferred to hydrogen pipelines. The complexity lies in a large variety of materials (low alloyed steels), pipeline diameters and corresponding welded joints. The material compatibility of materials in used (repurposed NG-pipelines) and new condition must be investigated. Particularly for repurposed/used pipelines the effect of a pre-matured/corroded inner surface and sometimes insufficient documentation of the material “history” needs to be considered. An overview on ongoing and completed R&D-projects with respect to repair concepts for hydrogen pipelines and hydrogen effects on pipeline materials is given. The focus hereby lies on possible methods of material testing and modeling. Its current difficulties, limits and possible solution will be discussed. T2 - IIW Intermediate Meeting, Com. II-A CY - Incheon, Republic of Korea DA - 12.03.2024 KW - Hydrogen KW - Repair welding KW - Pipelines KW - In-service PY - 2024 AN - OPUS4-59674 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Hydrogen trap characterization in 200 and 1,000 bar charged CoCrNi medium entropy alloy compared to steel AISI 316L N2 - Multiple principal element alloys (MPEAs) represent a new class of metallic materials. MPEAs, such as the CoCrNi medium entropy alloy (MEA), have attracted considerable research attention as potential materials to replace, for example, austenitic steels in high-pressure hydrogen environments. Due to the relatively new alloy concept, studies on the specific hydrogen diffusion and trapping behavior of high-pressure hydrogen-charged CoCrNi MEAs are rare so far. For this reason, a CoCrNi-MEA was investigated and compared to an austenitic stainless steel, AISI 316L. Both materials were subjected to high pressure hydrogen loading for two different pressures: 200 bar and 1,000 bar. After charging, thermal desorption analysis (TDA) was used with three heating rates from 0.125 K/s to 0.500 K/s to clarify the specific hydrogen desorption and trapping behavior. To the best of our knowledge, this study is the first to characterize hydrogen diffusion and trapping in 1,000 bar high-pressure charged CoCrNi. For this purpose, the underlying TDA spectra were analyzed in terms of peak deconvolution into a metallurgically justifiable number of defined peaks. The individual peak temperatures and activation energies “EA” were calculated. The following conclusions can be drawn from the results obtained: (1) Exposure to 200 bar or 1,000 bar leads to an increase in hydrogen absorption, regardless of the material investigated, expressed by a significantly increased desorption rate at 1,000 bar. However, the effusion peaks typically occur only at high temperatures. The (2) TDA showed that a four-peak deconvolution scenario was sufficient to describe the trapping behavior and the "EA" indicated the dominance of irreversible traps. In addition, the average trapping energy is higher than in the 316L. The (3) charge pressure related hydrogen solubility was in the order of: CoCrNi-MEA < 316L for both pressures and (4) charging at 1000 bar results in an average concentration of 49 wt.ppm (CoCrNi-MEA) and > 75 wt.ppm (316L). In summary, the CoCrNi-MEA was characterized by a reduced solubility, but very deep entrapment compared to the 316L. For this reason, further application potentials of the MEA may arise. T2 - FEMS Euromat 2025 - 18th European Congress and Exhibition on Advanced Materials and Processes CY - Granada, Spain DA - 15.09.2025 KW - Medium entropy alloy KW - Hydrogen KW - Trapping KW - Diffusion KW - High-pressure charging PY - 2025 AN - OPUS4-64160 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Component test for the assessment of in-service welding on/onto pressurized hydrogen pipelines N2 - Hydrogen is the energy carrier of tomorrow and requires a reliable large-scale transport infrastructure. In addition to new pipelines, the conversion of existing natural gas (NG) pipeline grids is an essential part. The transport of hydrogen is fundamentally different from that of NG, as hydrogen can be absorbed into the pipeline material. Given the effects of hydrogen embrittlement, the material compatibility (low alloy steels in a wide range of strengths and thicknesses) must be investigated. However, pipelines e.g. require maintenance or the need for installation of additional outlets with the necessity of welding on/onto the pipelines while they are still in service, i.e. with gas flow under high pressure, such as the well-known "hot tapping". This in-service welding poses challenges for hydrogen operations. The challenge can be roughly divided into the possible austenitization of the inner pipe material exposed to hydrogen, the welding itself, which causes an increased temperature range. Both lead to a significant increase in hydrogen solubility and diffusivity compared to room temperature. In addition, possible surface reactions of the present iron oxides (e.g. magnetite or hematite) with the hot hydrogen should be considered. In this context, the knowledge of hydrogen pipelines is scarce due to the lack of operational experience. Fundamental experimental investigations are required to investigate the transferability from NG to hydrogen pipeline grids. For this reason, the present study presents a specially designed mock-up / demonstrator concept for the realistic assessment of the welding process conditions. The mock-up was designed to allow in-situ temperature measurement during the welding process as well as ex-post sample extraction for quantification of the absorbed hydrogen concentration. For safety reasons, the required volume of pressurized hydrogen was limited by inserting a solid cylinder to ensure a 1 cm thick layer of hydrogen gas. Welding experiments on the DN60 and DN200 pressurized mock-ups showed the possibility of safe welding on or onto pressurized hydrogen pipelines. Indeed, the austenitizing temperature was reached on the inner surface of the pipeline, especially on thinner-walled pipelines, using current welding parameter recommendations. This corresponded to an increased hydrogen uptake in the welded area of several ppm. From this point of view, the suggested component concept is a viable strategy for the screening of several materials and welding parameter combinations under realistic operational conditions. T2 - FEMS Euromat 2025 - 18th European Congress and Exhibition on Advanced Materials and Processes CY - Granada, Spain DA - 15.09.2025 KW - In-service welding KW - Pipeline KW - Hydrogen KW - Component test PY - 2025 AN - OPUS4-64159 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Joining technologies for hydrogen components: current need and future perspectives N2 - The study provides an overview of the aspects of joining and its importance in manufacturing of components for the more and more important field of hydrogen as key factor for the energy transition to a decarburized future. To this end, the fundamentals of the technology fields of hydrogen production, storage, transport, and application are presented and the state of the art of manufacturing of components for hydrogen technologies by joining is summarized. Based on representative examples from practice, research and development, the importance of joining technology in hydrogen technologies is clearly highlighted and perspectives for the future are derived. From a macroeconomic perspective, the focal points, or trends of joining technologies here include: the erection of new infrastructure for hydrogen storage and transport, and the safe conversion of existing natural gas infrastructure and its challenges for welded materials. In addition, we show the problems that are anticipated with in-service repair welding of hydrogen pipelines. In hydrogen applications, the efficient mass production of fuel cells and electrolysers is becoming increasingly important. For that reason, the importance of additive manufacturing is highlighted. Finally, the challenges for technical regulations and standardization by using hydrogen are shown. T2 - AJP 2023: 3rd International Conference on Advanced Joining Processes 2023 CY - Braga, Portugal DA - 19.10.2023 KW - Hydrogen KW - Infractstructure KW - Joining KW - Welding KW - Research PY - 2023 AN - OPUS4-58674 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Welding of in service hydrogen pipelines for repair and maintenance purposes Concepts and Challenges N2 - Hydrogen will make a decisive contribution to a sustainable large-scale energy supply, the transport of which will be based on long-distance pipeline grids. Previous material compatibility studies have shown that the currently used low-alloy pipe steels are generally suitable for hydrogen pipelines. However, this cannot be directly transferred to the case of repair welding. For technical and economic reasons, welding work on hydrogen pipelines in service is usually carried out during operation under continuous pressure and gas flow. In this context, concepts such as hot tapping and stoppling are well established in natural gas (NG) grids and crude oil transportation. In hot tapping, a pressurized pipeline is drilled by flanging a sealed, pressure-tight system consisting of a shut-off valve and drilling equipment. For this purpose, sleeves (made of preformed cylindrical half-shells) must be welded by longitudinal seams and then welded to the product-carrying pipeline by circumferential girth welds. Preheat temperatures of approximately 100 °C must be maintained for most manual metal arc (MMA) / shielded metal arc welding (SMAW) and 250 °C for the interpass temperature in multi-pass welding. This is particularly important for thin-walled pipelines because the austenitizing temperature is exceeded on the inside of the pipeline when the girth welds are welded. As a result, significantly higher hydrogen absorption in the pipeline steel is expected, with possible degradation of mechanical properties or cracking. T2 - MSE 2024: International Materials Science and Engineering Congress CY - Darmstadt, Germany DA - 24.09.2024 KW - Hydrogen KW - Repair welding KW - Pipelines KW - In-service PY - 2024 AN - OPUS4-61155 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Thickness and microstructure effect on hydrogen diffusion in creep-resistant 9 % Cr P92 steel and P91 weld metal N2 - Martensitic 9 %-Cr steels like P91 and P92 show susceptibility to delayed hydrogen assisted cracking depending on their microstructure. In that connection, effective hydrogen diffusion coefficients are used to assess the possible time-delay. The small number of available diffusion coefficients varies already at room temperature by several orders of magnitude (mostly regarded as result of present microstructure). Especially P91 weld metal diffusion coefficients are rare so far. For that reason, electrochemical permeation experiments had been conducted using P92 base metal and P91 weld metal (in as-welded and heat-treated condition) with different thicknesses. The diffusion coefficients are calculated by two methods (time-lag and inflection point method) were performed. The results show that, despite of microstructural effects, the sample thickness must be considered as it influences the calculated diffusion coefficients. Finally, the comparison of calculated and measured hydrogen concentrations (determined by carrier gas hot extraction) enables the identification of realistic diffusion coefficients. T2 - IIW Annual Assembly, Meeting of Commission IX-C CY - Online meeting DA - 15.07.2021 KW - Creep-resistant steel KW - Diffusion KW - Electrochemical permeation KW - Hydrogen KW - Welding PY - 2021 AN - OPUS4-53048 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Hydrogen embrittlement of steels N2 - Hydrogen assisted cracking of metals is a serious issue in the safety of components, espcially in case of welding. The current presentation gives an overview on specialized testing procedures at Department 9 including the quantitative determination of hydrogen. T2 - HYDROGENIUS BAM Joint Hydrogen Symposium CY - Online meeting DA - 06.07.2021 KW - Hydrogen KW - Embrittlement KW - Degradation KW - Carrier gas hot extraction KW - Welding PY - 2021 AN - OPUS4-53049 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Standardization and examples for R & D activities on hydrogen technologies with respect to testing procedures in Germany N2 - This contribution briefly summarizes the standardization activities in accordance with the "Nationale Roadmap Wasserstofftechnologien" and presents selected results on the activities in Germany with scope on hydrogen transport in pipelines. The talk was given during a panel discussion to set-up a steering committee for standardization for hydrogen pipelines and welding , coordinated by the International Institute of Welding. T2 - IIW Annual Assembly, Meeting of Commission XI CY - Singapore DA - 19.07.2023 KW - Hydrogen KW - Welding KW - Pipelines KW - Standardization KW - Research PY - 2023 AN - OPUS4-57976 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Intended weld repair of in service hydrogen pipelines N2 - In the course of tomorrow's hydrogen-based energy transition, the construction of the corresponding infrastructure will play a central role. In that context, large diameter long-distance transmission pipelines for hydrogen will be the backbone in the European Union with service pressures from 70 to 90 bar (e.g., de-pending on national regulations). It is a major goal to repurposing the existing natural gas (NG) infrastructure despite the necessity of new pipelines. From that point of view repair welding or further welding of branch pipe etc. can be necessary during in-service, i.e., permanent flow of pressurized hydrogen. The reason is that a shut-down of large diameter pipelines is not easy or sometimes merely impossible. At the moment, it is entirely open if current repair welding procedures for NG pipe-lines can be transferred to pure hydrogen pipelines. For that reason, a collaborative project between BAM, DVGW (German Association for Gas and Water Professions) and a large number of gas grid operators, pipeline manufacturers and construction companies was initiated in 2023 to answer questions on: (1) How many hydrogen is additionally absorbed during the preheating and maintaining at interpass temperature under remaining operational pressures? (2) Is the hydrogen concentration sufficient to reach a critical condition? (3)Which material and weld microstructure are the most susceptible? (4) Is there a difference in the repair welding behavior of NG pipelines with materials in “used” condition? (5) Which welding parameters and joint dimensions must be ensured for safe repair welding? The final aim of this project is the publication of a recommended practice for repair welding of in-service hydrogen pipelines. For that reason, the present study gives an overview on: (A) current practice in repair welding of in-service pipelines and (b) plans for hydrogen pipelines and first results of international research projects. T2 - IIW Annual Assembly, Meeting of Commission XI CY - Singapore DA - 19.07.2023 KW - Hydrogen KW - Repair Welding KW - Pipelines KW - Research PY - 2023 AN - OPUS4-57975 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Trapping in T24 steel weld joints – Effects on activation energy for hydrogen diffusion during TDA N2 - Failure cases in the past decade exhibited severe cracking in T24 welds and showed that generally hydrogen-assisted cracking (HAC) occurring up to 200°C cannot be excluded. A basic understanding is necessary on how hydrogen diffusion is influenced by the weld process. In this regard, both weld microstructures HAZ and weld metal have particular influence on hydrogen diffusion compared to the base material. In general, hydrogen diffusion at a certain temperature is described by diffusion coefficients representing an effective value of combined lattice diffusion and effects of reversible hydrogen traps. Those traps are typically precipitates, interstitials, grain boundaries and so on. A common approach to describe the trap character and its effect on diffusion is the determination of so-called activation energy. This can be done by respective thermal desorption analysis (TDA) with linear heating. In the present study, different T24 as-welded microstructures (BM, HAZ, WM) were investigated. For that purpose, electrochemically hydrogen charged specimens were analyzed by TDA with linear heating using a mass spectrometer for detection of ultra-low hydrogen amounts. The results showed that typically the as-welded HAZ had higher energy traps than the tempered base material. Nonetheless two important effects were ascertained: (1) it is strictly necessary to monitor the sample temperature due to its great impact on the hydrogen desorption peak temperature and (2) the real heating rate in the specimen vs. the applied heating rate has to be considered. Both influence the calculated activation energy, i.e. the assigned hydrogen trap character (moderate or strong trap), which changed up to a factor of two in terms of the calculated activation energy. This effect can be much more important compared to the microstructure effect itself. Hence, suitable experimental boundary conditions should be mandatory for the determination of hydrogen trap kinetics. T2 - Intermediate Meeting of IIW Commission C-II-A "Metallurgy of Weld Metal" CY - Trollhättan, Sweden DA - 06.03.2017 KW - Hydrogen KW - Trapping and diffusion KW - Thermal desorption analysis KW - Microstructure KW - Activation energy PY - 2017 AN - OPUS4-39401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Diffusion and trapping of gaseous hydrogen charged CoCrFeMnNi-HEA vs. austenitic steel AISI 316L at pressure up to 1000 bar N2 - First studies on the mechanical behavior of high-entropy alloys (HEAs) in high-pressure hydrogen environment are available. In contrast, the underlying hydrogen absorption, diffusion and trapping in these HEAs like the Cantor-alloy was less in the scientific scope so far. For that reason, the CoCrFeMnNi-HEA was compared to a conventional AISI 316L austenitic steel, by exposing to high-pressure hydrogen charging at 200 bar and very-high pressure at 1,000 bar. Thermal desorption analysis (TDA) was applied with different heating rates (0.125 K/s to 0.500 K/s). The underlying TDA spectra were analyzed in terms of a reasonable peak deconvolution to into a defined number of peaks and the calculation of the activation energies for the respective and predominant hydrogen trap sites. Both materials show a comparable hydrogen diffusivity. The obtained activation energies suggest that in case of the CoCrFeMnNi-HEAs an interaction of the austenitic phase as well as the direct atomic bonding of hydrogen to the metal atoms are the dominant traps, since “impurities” such as carbides or inclusions are only present in trace amounts. Available literature suggests that the Cr and Mn-content is here of special interest for the direct hydrogen bonding at solute atoms. T2 - MSE 2024: International Materials Science and Engineering Congress CY - Darmstadt, Germany DA - 24.09.2024 KW - High-entropy alloy KW - Hydrogen KW - Trapping KW - Diffusion KW - High-pressure charging PY - 2024 AN - OPUS4-61156 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Influence of welding parameters on diffusible hydrogen content in high-strength steel welds using modified spray arc N2 - In order to satisfy the growing requirements towards lightweight design and resource efficiency in modern steel constructions, e.g. mobile cranes and bridges, high-strength steels with typical yield strength ≥ 690 MPa are coming into use to an increasing extent. However, these steels require special treatment in welding. The susceptibility for degradation of the mechanical properties in presence of hydrogen increases significantly with increasing yield strength. In case of missing knowledge about how and which amount of hydrogen is uptaken during welding, hydrogen assisted cracking (HAC) can be a negative consequence. Moreover, modern weld technology like the modified spray arc process enables welding of narrower weld seams. In this context, a reduced number of weld beads, volume and total heat input are technical and economic benefits. This work presents the influence of welding parameters on the diffusible hydrogen content in both singlepass and multi-layer welds. Different hydrogen concentrations were detected by varied contact tube distance, wire feed speed, arc length as well as varied arc type (transitional arc and modified spray arc). The results show, that all welding parameters have significant influence on the diffusible hydrogen concentration in the single-pass welds. By increasing the number of weld beads in case of multi-layer welding, the hydrogen concentration have been substantially reduced. Whereby, differences in hydrogen concentrations between both arc types are present. T2 - 70th IIW Annual Assembly, Commission II-A CY - Shanghai, People's Republic of China DA - 25.06.2017 KW - Hydrogen KW - MAG Welding KW - High-strength steels KW - Process parameters PY - 2017 AN - OPUS4-40953 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Characterization of hydrogen trapping in a CoCrFeMnNi high-entropy alloy charged up to 1000 bar high-pressure hydrogen N2 - First studies on the mechanical behavior of high-entropy alloys (HEAs) in high-pressure hydrogen environment are available. In contrast, the underlying hydrogen absorption, diffusion and trapping in these HEAs like the Cantor-alloy was less in the scientific scope so far. For that reason, the CoCrFeMnNi-HEA was compared to a conventional AISI 316L austenitic steel, by exposing to high-pressure hydrogen charging at 200 bar and very-high pressure at 1,000 bar. Thermal desorption analysis (TDA) was applied with different heating rates (0.125 K/s to 0.500 K/s), see Fig. 1a to d. The underlying TDA spectra were analyzed in terms of a reasonable peak deconvolution to into a defined number of peaks and the calculation of the activation energies for the respective and predominant hydrogen trap sites. Both materials show a comparable hydrogen diffusivity. The obtained activation energies suggest that in case of the CoCrFeMnNi-HEAs an interaction of the austenitic phase as well as the direct atomic bonding of hydrogen to the metal atoms are the dominant traps, since “impurities” such as carbides or inclusions are only present in trace amounts. Available literature suggests that the Cr and Mn-content is here of special interest for the direct hydrogen bonding at solute atoms. In addition, the trap occupancy rate must be considered in terms of a pressure-related hydrogen absorption. The derived apparent hydrogen solubility was in the order: 316L < CoCrFeMnNi-HEA for both charging pressures. Especially, the 1,000 bar values lead to noteworthy results with > 70 wt.ppm for the AISI 316L and >130 wt.ppm for the CoCrFeMnNi. In fact, both the hydrogen diffusion and trapping data on gaseous high-pressure hydrogen charged HEAs are rare so far. The results of the present study allow a deeper understanding of hydrogen trapping in the regarded CoCrFeMnNi-system. T2 - 78th IIW Annual Assembly and International Conference CY - Genoa, Italy DA - 26.06.2025 KW - Hydrogen KW - Thermal desorption analysis KW - High-pressure charging KW - Trapping KW - Diffusion PY - 2025 AN - OPUS4-63542 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Thickness and microstructure effect on hydrogen diffusion in creep-resistant 9 % Cr P92 steel and P91 weld metal N2 - Martensitic 9 %-Cr steels like P91 and P92 show susceptibility to delayed hydrogen assisted cracking depending on their microstructure. In that connection, effective hydrogen diffusion coefficients are used to assess the possible time-delay. The small number of available diffusion coefficients varies already at room temperature by several orders of magnitude (mostly regarded as result of present microstructure). Especially P91 weld metal diffusion coefficients are rare so far. For that reason, electrochemical permeation experiments had been conducted using P92 base metal and P91 weld metal (in as-welded and heat-treated condition) with different thicknesses. The diffusion coefficients are calculated by two methods (time-lag and inflection point method) were performed. The results show that, despite of microstructural effects, the sample thickness must be considered as it influences the calculated diffusion coefficients. Finally, the comparison of calculated and measured hydrogen concentrations (determined by carrier gas hot extraction) enables the identification of realistic diffusion coefficients. T2 - IIW Intermediate Meeting, Comm. IX-C "Welding of creep and heat-resistant materials" CY - Online meeting DA - 08.03.2021 KW - Hydrogen KW - Welding KW - Diffusion KW - Creep-resistant steel KW - Electrochemical permeation PY - 2021 AN - OPUS4-52239 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Diffusion in high-pressure hydrogen charged multi-principal element alloys CoCrFeMnNi and CoCrNi vs. AISI 316L N2 - Multi-principal element alloys (MPEAs) are innovative materials that have attracted extensive research attention within the last decade. MPEAs are characterized by a solid solution of equiatomic metallic elements. Depending on the number of elements, they are also referred as high entropy alloys (HEAs with n ≥ 4 elements like CoCrFeMnNi) and medium-entropy alloys (MEA with n = 3 elements CoCrNi). Depending on the alloy concept, MPEAs show exceptional properties in terms of mechanical performance or corrosion resistance at extreme environments. In that connection, hydrogen and its challenges for the most metallic materials gets more and more important. MPEAs are candidate materials for the substitution of conventional materials like austenitic stainless steels e.g., at very high-pressure up to 1000 bar. Those pressures are typically reached in valves or compressors for refueling of tanks with operational pressure of 700 bar. So far, the susceptibility of HEA/MEAs to hydrogen assisted cracking (if any) and the especially the underlying hydrogen uptake and diffusion was not within the scientific scope and not investigated in detail yet. For that reason, we focused on the hydrogen absorption the characterization of the hydrogen diffusion and trapping at elevated temperatures in a CoCrFeMnNi-HEA (each element with 20 at.-%) and CoCrNi-MEA, each element with 33.3 at.-%). As reference grade, the commercially available austenitic stainless steel AISI 316L was investigated. High-pressure hydrogen charging was conducted at different pressures in autoclave environment with maximum value of 1,000 bar. Thermal desorption analysis (TDA) via carrier gas hot extraction with coupled mass spectrometry was used with a max. heating rate of 0.5 K/s up to 650 °C. The measured desorption spectra of the different samples were deconvoluted into a defined number of individual peaks. The individually calculated peak temperatures allowed the definition of activation energies for predominant trap sites in the respective materials as well as the percentage share of the totally absorbed hydrogen concentration. The results present for the first time the complex interaction of both MPEAs and high-pressure hydrogen charging. A deconvolution of four peaks was selected and a main desorption peak was identified the dominant hydrogen trap containing the biggest share of the absorbed hydrogen concentration. The chemical composition an austenitic phase of both MPEAs is responsible for delayed hydrogen diffusion and strong, but mostly reversible, trapping. The comparison with the 316L samples showed significantly higher activation energies in the MPEAs, whereas hydrogen was also trapped at very high extraction temperatures. The absorbed maximum hydrogen concentration at 1,000 bar was 130 ppm for the CoCrFeMnNi-HEA, 50 ppm for the CoCrNi-MEA and 80 ppm for the 316L. It is interesting that the CoCrFeMnNi-HEA has obviously a way higher trapping capability compared to the conventional austenitic 316L, which could be a major advantage in terms of resistance to hydrogen assisted cracking. T2 - 47th MPA-Seminar CY - Stuttgart, Germany DA - 10.10.2023 KW - High-entropy alloy KW - Hydrogen KW - Diffusion KW - Thermal desorption analysis KW - Multiple-principal element alloy PY - 2023 AN - OPUS4-58675 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Development of a component test for assessment of delayed hydrogen assisted cracking susceptibility of thick walled submerged arc welded high strength offshore steels N2 - Offshore Wind Turbines (OWT) are a key factor in tomorrow's sustainable energy generation. The ever-increasing installation depth and weight of OWTs require suitable foundation concepts such as monopiles or tripods. Typically, mild steels such as S420ML are used with plate thicknesses of up to several hundred mm, resulting in high restraints in the welded joints. The large plate thickness requires high-efficiency welding processes such as submerged arc welding (SAW) with multiple wires. Due to the very high stiffness and plate thickness of the large-scale offshore structure, a susceptibility to time-delayed hydrogen assisted cracking (HAC) may occur. The evaluation of this crack susceptibility is very complex due to the component size and stiffness of real offshore structures. For this purpose, a near-component test geometry was developed to transfer the real stiffness conditions to laboratory (i.e. workshop) scale. The 350 kg mock-up studied consisted of heavy plates (thickness 50 mm, seam length 1,000 m) joined by a 22-pass submerged-arc weld. Additional stiffeners simulated the effect of high restraint or shrinkage restraint of the weld. Extreme scenarios of hydrogen absorption during welding were simulated by using flux in dry (HD < 5 ml/100g Fe) and wet (HD > 15 ml/100g Fe) conditions. Weld residual stresses were determined using a robotic X-ray diffractometer. Areas of critical tensile residual stress (at the level of the yield strength) were found in the weld metal and in the heat affected zone, suggesting that these weld sub-zones are the most critical in the case of hydrogen ingress. To identify possible delayed cracking, the welds were tested by phased array ultrasonic testing (PAUT) after welding, 6 h, 12 h, 24 h, and a maximum of 48 h. Summarized, no significant occurrence of HAC was detected, indicating the high crack resistance of the welded joint, i.e., a suitable combination of base material, welding consumable and parameters. T2 - MSE 2024: International Materials Science and Engineering Congress CY - Darmstadt, Germany DA - 24.09.2024 KW - Hydrogen KW - Offshore wind turbine KW - Component test KW - Submerged arc welding KW - Minimum waiting time PY - 2024 AN - OPUS4-61154 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Assessment of in-service welding conditions for pressurized hydrogen pipelines via component test N2 - Hydrogen is the energy carrier of tomorrow. This requires a reliable transport infrastructure with the ability to carry large amounts of hydrogen e.g. for steel industry or chemical industry. The conversion of existing natural gas (NG) grids is an essential part of the worldwide hydrogen strategies, in addition to the construction of new pipelines. In this context, the transportation of hydrogen is fundamental different from NG as hydrogen can be absorbed into the pipeline material. Given the well-known effects of hydrogen embrittlement, the compatibility of the materials for the intended pipelines must be investigated (typically low alloy steels in a wide range of strengths and thicknesses). However, pipelines require frequent maintenance, repair or the need for installation for further outlets. In some cases, it is necessary to perform welding on or onto the pipelines while they are still in service, i.e. with active gas flow under high pressure, e.g. such as the well-known “hot tapping”, see Fig. 1a. This in-service welding causes challenges for hydrogen operations in terms of additional hydrogen absorption during welding and the material compatibility. The challenge can be roughly divided into the possible austenitization of the inner pipe material exposed to hydrogen, which can lead to sufficient hydrogen absorption, and the welding itself, which causes an increased temperature range. Both lead to a significant increase in hydrogen solubility and diffusivity of the respective materials compared to room temperature. In this context, knowledge about hot tapping on hydrogen pipelines is scarce due to the lack of operating experience. Fundamental experimental investigations are required to investigate the transferability from NG to hydrogen pipeline grids. For this reason, the present study introduces a specially designed mock-up / demonstrator concept for the realistic assessment of the welding processing conditions, see Fig. 1b. The mock-up was designed to enable in-situ temperature measurement during welding as well as ex-post extraction of samples for the quantification of the absorbed hydrogen concentration, see Fig. 1c. For safety measures, the necessary pressurized hydrogen volume was limited by the insertion of a solid cylinder ensuring a 1 cm hydrogen gas layer. Welding experiments on the pressurized mock-ups with the diameters DN50 and DN200 have shown that the austenitization temperature can be reached on the inner surface of the pipeline, especially on thinner-walled pipelines, using current welding practices. This corresponds to an increased hydrogen uptake in the welded area of several ppm T2 - 1st Conference on Hydrogen in Materials Science and Engineering (H2-MSE) CY - Siegburg, Germany DA - 11.02.2025 KW - Hydrogen KW - Pipeline KW - In-service welding KW - Component test PY - 2025 AN - OPUS4-62544 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Specimen temperature during CGHE and influence on hydrogen determination N2 - Hydrogen determination in weld seams is standardized in ISO 3690. In accordance to this standard, a defined time for hydrogen collection has to be anticipated for different extraction temperatures. In other words, the temperature is the most important value that has to be monitored in addition to the aimed hydrogen determination. The specimen geometry has influence on the real sample temperature during CGHE vs. the adjusted furnace temperature. This presentation gives a short summary on possible influences on the "correct" hydrogen determination temperature during carrier gas hot extraction (CGHE) using infrared radiation driven furnace. The main findings are: (1) specimen surface is important in terms of polished or oxidized condition, (2) specimen geometry is important for fast heating, (3) PID-values of control software are a considerable influence to accelerate the heating process depite thick specimens and (4) independent sample temperature determination before CGHE is strongly recommended. T2 - Intermediate Meeting of IIW Subcommission II-E CY - Genoa, Italy DA - 05.03.2018 KW - Hydrogen KW - Welding KW - Carrier gas hot extraction KW - Temperature KW - Measurement PY - 2018 AN - OPUS4-44427 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Determination of inner pipe surface temperatures during in-service welding on hydrogen pipelines by means of component-like mock up experiments N2 - Hydrogen is considered as one of the most important energy carriers in the future. The necessary large-scale transport over long distances requires a suitable pipeline infrastructure. Current plannings encompass a dual-way strategy of repurposing existing natural gas (NG) pipelines, supplemented by the construction of new hydrogen pipelines. In some cases, such as necessary grid extensions or installation of bypasses in case of repair work, techniques like “hot tapping” are applied. These techniques include so-called in-service welding on pressurized pipelines and are state-of-the-art for NG grids and oil pipelines. The existing NG pipeline grid consists of a wide range of materials with different strengths, diameters, and wall thicknesses. In this context, the material compatibility is crucial. The main difference between hydrogen and NG is that hydrogen can both penetrate the material and cause hydrogen embrittlement. In that connection, in-service welding encompasses elevated temperatures for a certain time during the typically multi-layer welding process. Locally even austenitization temperature can be reached or surpassed. Austenite has a higher hydrogen solubility at a significantly lower diffusion rate, which could lead to a critical hydrogen accumulation. Especially the inner pipe surface temperature is from utmost interest, as this interface is exposed to the pressurized hydrogen (up to 100 bar). However, direct measurement of the locally occurring temperatures is very challenging. For this reason, a component-like geometry was developed. The geometry consists of a pipeline segment with a metal sheet joined to the pipe segment, representing similar heat dissipation conditions as in the field. In addition, typical welding parameters were applied that are currently used in the NG grid. This allows the welding of realistic multi-layer fillet welds on the outer pipe wall with simultaneous temperature measurement using manifold thermocouples at defined positions: (1) adjacent to the weld seam on the outer pipe surface, (2) on the inner pipe surface and (3) on the welded metal sheet. To ensure realistic conditions, manual shielded metal arc welding (SMAW) and gas tungsten arc welding (GTAW) was investigated. The effects of different wall thicknesses and welding heat inputs on the temperature distribution and peak temperatures achieved on the inner pipe surface during welding vary depending on the chosen method. Peak temperatures above austenitization temperature up to 1078 °C have been measured on L245 pipes with wall thickness of 3.6 mm. For pipes made from higher strength materials, such as L485, with a wall thickness of 8 mm, peak temperatures between 607 °C and 755 °C were recorded. Temperature and austenitization directly affects hydrogen diffusivity and solubility, showing the importance of the findings. The temperature profile and cooling conditions influence the mechanical properties of the material as well. For this reason, metallurgical investigations are carried out to assess the hardness and microstructure of the welds. Hardening up to 248 HV10 was detected in the heat-affected zone (HAZ) of the top layer, which could lead to a locally increased susceptibility to hydrogen assisted cracking. Meanwhile, the minimum hardness found in the HAZ of the root layer was as low as 144 HV10, indicating a softening. The results of this study provide valuable insights into the suitability of existing materials and geometries for hydrogen transport. Secondly, the data collected will serve as a basis for planned numerical simulations to further improve knowledge and optimize welding processes to ensure the integrity and safety of hydrogen pipelines. T2 - IIW Intermediate Meeting, Com. II-A CY - Trollhättan, Sweden DA - 10.03.2025 KW - Testing KW - In-service welding KW - Hydrogen KW - Pipelines PY - 2025 AN - OPUS4-62690 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Component test for simplified testing of hydrogen‐assisted delayed cold cracking of high‐strength, submerged arc‐welded offshore steel structures N2 - Offshore Wind Turbines (OWT) are a key factor in tomorrow's sustainable energy generation. The ever-increasing installation depth and weight of OWTs require suitable foundation concepts such as monopiles or tripods. Typically, mild steels such as S420ML are used with plate thicknesses of up to several hundred mm, resulting in high restraints in the welded joints. The large plate thickness requires high-efficiency welding processes such as submerged arc welding (SAW) with multiple wires. Due to the very high stiffness and plate thickness of the large-scale offshore structure, a susceptibility to time-delayed hydrogen assisted cracking (HAC) may occur. The evaluation of this crack susceptibility is very complex due to the component size and stiffness of real offshore structures. For this purpose, a near-component test geometry was developed to transfer the real stiffness conditions to laboratory (i.e. workshop) scale. The 350 kg mock-up studied consisted of heavy plates (thickness 50 mm, seam length 1,000 m) joined by a 22-pass submerged-arc weld. Additional stiffeners simulated the effect of high restraint or shrinkage restraint of the weld. Extreme scenarios of hydrogen absorption during welding were simulated by using flux in dry (HD < 5 ml/100g Fe) and wet (HD > 15 ml/100g Fe) conditions. Weld residual stresses were determined using a robotic X-ray diffractometer. Areas of critical tensile residual stress (at the level of the yield strength) were found in the weld metal and in the heat affected zone, suggesting that these weld sub-zones are the most critical in the case of hydrogen ingress. To identify possible delayed cracking, the welds were tested by phased array ultrasonic testing (PAUT) after welding, 6 h, 12 h, 24 h, and a maximum of 48 h. Summarized, no significant occurrence of HAC was detected, indicating the high crack resistance of the welded joint, i.e., a suitable combination of base material, welding consumable and parameters. T2 - MPA Seminar 2024 - Materials, Processes, Applications CY - Stuttgart, Germany DA - 08.10.2024 KW - Hydrogen KW - Offshore wind turbine KW - Component test KW - Submerged arc welding KW - Minimum waiting time PY - 2024 AN - OPUS4-61323 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Joining Processes in Hydrogen Technologies - Current need and future R&D activites, a review N2 - This study gives an overview on the important field of joining processes for component fabrication in hydrogen technologies. For that reason, the current need and future research and developement activites are highlighted for the different technological field of hydrogen generation, storage, transport and use. In addition, the emerging field of additive manufacturing is included. Finally, some remarks are given for necessary changes in the standardization and its challenges. T2 - 46th Seminar - Additive Manufacturing, Hydrogen, Energy, Integrity CY - Online meeting DA - 12.10.2021 KW - Hydrogen KW - Joining process KW - Welding KW - Review KW - Research and Development PY - 2021 AN - OPUS4-53554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Joining processes for components in hydrogen technologies: Current need and future importance N2 - This presentation gives an overview on the importance of joining processes for component fabrication in hydrogen technologies. For that reason, the current need and future research and developement activites are highlighted for the three technological fields: hydrogen storage, transport and use (in terms of the emerging field of additive manufacturing). Finally, some remarks are given for necessary changes in the standardization. T2 - IIW Intermediate Meeting, Comm. II-A "Welding Metallurgy" CY - Online meeting DA - 17.03.2022 KW - Hydrogen KW - Welding KW - Research KW - Review KW - Additive manufacturing PY - 2022 AN - OPUS4-54488 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Welding (and joining) technologies for the hydrogen economy - a short overview N2 - This study gives an overview on the important field of joining processes for component fabrication in hydrogen technologies. The current main issues and future perspectives are highlighted for the different technological field of hydrogen generation, storage, transport and use. In addition, the emerging field of additive manufacturing is included. Some remarks are given for standardization and regulations. T2 - Meeting of the European Welding Association (EWA), Executive Committee (EC) 1 CY - Frankfurt am Main, Germany DA - 22.03.2023 KW - Hydrogen KW - Welding KW - Research KW - Study PY - 2023 AN - OPUS4-57222 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Component test for simulation of in-service welding on hydrogen pipelines N2 - Hydrogen is set as the energy carrier of tomorrow and most countries will achieve large-scale hydrogen transport through the conversion of the natural gas (NG) grid and the construction of new pipelines. The interaction between hydrogen and the pipeline materials differs fundamentally from that of NG, as hydrogen is readily absorbed into the material. Considering the possible hydrogen embrittlement (HE), the compatibility of the pipeline materials (low-alloyed steels with a wide strength/thickness range) must be investigated. However, pipelines require intervention for maintenance, repair, or grid expansion with welding on/onto the pipelines while in service, i.e. the well-known "hot tapping" and "stoppling". The challenges compared to NG can be broadly divided into the possible austenitization of the inner pipe material exposed to hydrogen and the welding itself. Both result in a significant increase in hydrogen solubility and could potentially pose challenges in terms of HE. Emphasis is placed on the word "could" because knowledge of "hot tapping" on hydrogen pipelines is scarce due a lack of service experience. To this end, this study proposes a concept for a component-like demonstrator with the objectives: (1) safe feasibility of "hot tapping" on pressurized model hydrogen pipeline sections, (2) facilitate ex-post sample extraction for the purpose of quantifying the absorbed hydrogen concentrations, and (3) ensure in-situ temperature measurement during welding to monitor the pipeline surface temperature. For safety reasons in the event of an unintentional "burn-through", a solid cylinder was inserted in the demonstrator to restrict the hydrogen gas volume to a small, pressurized layer. Reference pipeline surface temperature measurements were ensured on comparable, unpressurized geometries. The investigated range of welding conditions was investigated for representative material/thickness combinations (DN60 to DN300), suggesting the feasibility of the demonstrator for the determination of reliable in-service welding conditions for both installed and new pipelines for hydrogen service. T2 - 49th MPA Conference CY - Stuttgart, Germany DA - 06.10.2025 KW - Hydrogen KW - Pipeline KW - In-service welding KW - Component test PY - 2025 AN - OPUS4-64317 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - "On how to influence your results" - A review on carrier gas hot extraction parameters for hydrogen determination in welded specimens N2 - Carrier gas hot extraction (CGHE) is a commonly applied technique for determination of hydrogen in welded joints using a thermal conductivity device (TCD) for quantitative measurement. The CGHE is based on the accelerated hydrogen effusion due to thermal activation at elevated temperatures. The ISO 3690 standard suggests different specimen geometries as well as necessary minimum extraction time vs. temperature. They have the biggest influence on precise hydrogen determination. The present study summarizes the results and experience of numerous test runs with different specimen temperatures, geometries and factors that additionally influence hydrogen determination. They are namely: specimen surface (polished/as-welded), limited TCD sensitivity vs. specimen volume, temperature measurement vs. effects of PID-furnace controller as well as errors due to insufficient data assessment. Summarized, the temperature is the driving force of the CGHE. Two different methods are suggested to increase the heating rate up the reach the desired extraction temperature without changing the experimental equipment. Suggestions are made to improve the reliability of hydrogen determination depended on the hydrogen signal stability during extraction accompanied by evaluation of the recorded data. Generally, independent temperature measurement with calibration specimens is useful for further data analysis, especially if this data is used for calculation of trapping kinetics by thermal desorption analysis (TDA). T2 - IIW Annual Assembly and International Conference 2018, Meeting of Commission II-E CY - Nusa Dua, Bali Island, Indonesia DA - 15.07.2018 KW - Carrier gas hot extraction (CGHE) KW - Welding KW - ISO 3690 KW - Hydrogen KW - Experimental design PY - 2018 AN - OPUS4-45520 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Hollow specimens as simplified approach for testing metallic materials under high pressure hydrogen development and utilization N2 - The hydrogen economy requires large-scale storage and transportation options like long-distance transmission pipelines. The applied materials (typically steels) must be carefully tested under different conditions (pressure, temperature, impact of impurities, etc.) for their suitability and service with hydrogen. In combination with mechanical load, as occurs in every gas network, hydrogen can induce degradation of the mechanical properties and promote finally resulting in embrittlement, i.e., the formation of cracks. The conventional testing procedures consist of autoclaves in which samples are strained under pressurized hydrogen. The test apparatus requires large amounts of hydrogen and thus a high level of safety and costs. In very specific cases, these tests might be replaced by simplified electrochemical charging. However, these test alternatives raise several questions regarding the equivalency of both testing scenarios. In the early 1980’s the idea of a so-called hollow tensile sample raised and was reinitiated 2021 in ISO TC 164 by T. Ogata (NIMS, Japan) and further developed (e.g. by Fraunhofer IWM, Germany). The idea was: the sample itself represents the autoclave instead of charging a sample from outside. For that reason, a hole is drilled through the sample and the inner surface is pressurized by hydrogen gas during the mechanical testing. Indeed, this represents the main advantage as no expensive pressure-resistant autoclave equipment for large H-volumes is necessary, which significantly reduces the safety-related issues and thus the high costs. In the following, we show recent activities at BAM Berlin on adaption of the hollow-specimen technique for slow strain rate testing (SSRT). The current research activities are focussed on macroscopic influences like the sample geometry, minimum necessary dimensions, and microscopic influences e.g., on the surface by the processing method (drill hole quality and geometric precision) as well as the gas pressure effect (mechanical deformation of surface in different media). T2 - FEMS EUROMAT 2023 CY - Frankfurt a. M., Germany DA - 04.09.2023 KW - Hydrogen KW - Hollow tensile specimen KW - High-pressure KW - Mechanical properties KW - Testing PY - 2023 AN - OPUS4-58220 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Hydrogen absorption and diffusion in T24 steel weld joints and effect on mechanical properties N2 - The present contribution summarizes results obtained from experiments with low-alloyed boiler steel grades T24 (CrMoV alloy), T22 (CrMo) and thermally simulated T24 HAZ microstructure and pure weld metal. The hydrogen absorption and diffusion behavior was investigated by permeation experiments and thermal desorption analysis (TDA). The results showed significant weld microstructure influence on diffusion by hydrogen trapping. Trapped hydrogen was determined in the T24 BM at temperatures up to 120 °C compared to 75 °C in the T22. In addition, the T24 HAZ showed decreased diffusion coefficients (at room temperature) of approximately one magnitude compared to the BM. For the mechanical properties, tensile tests were conducted with electrochemically hydrogen charged specimens and compared to results obtained from slow strain rate tests (SSRT) in high-temperature water up to 200 °C. The as-welded HAZ had remarkably increased susceptibility compared to the BM already at low hydrogen concentration of 1-2 ppm. The SSRT were conducted for free corrosion and acidic environment and confirmed this behavior at elevated temperatures for both HAZ microstructures of T24 and T22. Summarized, each weld microstructure has specific diffusion coefficients and shows different susceptibility to degradation of the mechanical properties, i.e. delayed hydrogen assisted cracking or stress corrosion cracking. T2 - NACE Italia - 2nd Conference & Expo 2018 CY - Genoa, Italy DA - 28.05.2018 KW - Hydrogen KW - Stress corrosion cracking KW - Welding KW - Creep-resistant steel KW - T24 / 7CrMoVTiB10-10 PY - 2018 AN - OPUS4-45080 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Additive manufacturing for components in hydrogen technologies N2 - With the introduction of a hydrogen-based energy and national economy, safety-relevant components for hydrogen technologies are becoming increasingly important. Characteristic of hydrogen technologies are, for example, harsh environmental conditions such as cryogenic or high-pressure storage, corrosion issues in fuel cells and electrolyzers, turbines, and many more. Additive manufacturing of components is becoming increasingly important and irreplaceable for the production of complex technical systems. Using the case studies of burners for gas turbines and electrodes and membranes for polymer (PEMFC) and solid oxide (SOFC) fuel cells, this article shows the potential of additive manufacturing of components. At the same time, however, the challenge of considering divergent mechanical properties depending on the direction of assembly in a "hydrogen-compatible" manner is also highlighted. Finally, the challenges posed by additive manufacturing and hydrogen for materials testing are highlighted under scenarios that are as realistic as possible. T2 - MPA-Workshop Hydrogen CY - Online meeting DA - 10.11.2022 KW - Additive manufacturing KW - Hydrogen KW - Technologies KW - Overview KW - Component PY - 2022 AN - OPUS4-56233 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Hydrogen diffusion in creep-resistant 9%-Cr P91 steel weld metal N2 - 9 %-Cr steel P91 is widely used in power plants due to the excellent creep-resistance. Components of this steel are typically welded and demand for careful welding fabrication, whereas a so-called post weld heat treatment (PWHT), must be conducted to increase the toughness and decrease the hardness of the martensitic as-welded (AW) microstructure. Before the PWHT, a hydrogen removal (or dehydrogenation) heat treatment is necessary as hardened AW martensitic microstructure is generally prone to delayed hydrogen assisted cracking (HAC). The microstructure and temperature dependent hydrogen diffusion is an important issue as it determines how long a potential crack-critical hydrogen concentration could remain in the microstructure. In this context, reliable hydrogen diffusion coefficients of P91 weld metal are rare. Hence, the diffusion behavior of P91 multi-layer weld metal was investigated in two different microstructure conditions: AW and further PWHT (760 °C for 4 h). Two different experimental techniques were used to cover a wide range of hydrogen diffusion temperatures: the electrochemical permeation technique (PT) at room temperature and the carrier gas hot extraction (CGHE) for a temperature range from 100 to 400 °C. From both techniques typical hydrogen diffusion coefficients were calculated and the corresponding hydrogen concentration was measured. It was ascertained that both heat treatment conditions show significant differences in hydrogen diffusivity. The biggest deviations were identified for room temperature. In this case, the AW condition shows significant hydrogen trapping and up to seven times lower diffusion coefficients. Additionally, PT investigations showed a preferred diffusion direction of hydrogen in the weld metal expressed by the diffusion coefficients and the permeability for both heat treatment conditions. The CGHE generally revealed lower diffusion coefficients for the AW microstructure up to 200 °C. In addition, the AW condition showed hydrogen concentrations up to 50 ml/100 g (considering electrochemical charging). Nonetheless, this hydrogen was not permanently (reversibly) trapped. Nonetheless, this temperature is approximately 100 °C below recommended dehydrogenation heat treatment (DHT). This has two main consequences: (I) in case of welding is interrupted or no DHT is conducted, a HAC susceptibility of hardened martensitic P91 weld metal cannot be excluded and (II) DHT can be conducted at temperatures around 200 °C below the recommended temperatures. T2 - IIW Annual Assembly, Meeting of Commission IX-C "Creep and heat resistant welds" CY - Bratislava, Slovakia DA - 07.07.2019 KW - Hydrogen KW - Diffusion KW - Weld metal KW - Microstructure KW - Post weld heat treatment PY - 2019 AN - OPUS4-48449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Hydrogen in weld joints - An underestimated risk? - Utilization potential of gas analytics versus safety of welded components N2 - Hydrogen was once called “the versatile embrittler” [1], which summarizes very well the effect on reduction of ductility and/or toughness in technical alloys like steel. In that connection, welding is one of the most important component fabrication technologies. During welding, hydrogen can be transferred to the weld pool from manifold sources (like contaminations, residuals at the surface, etc.). As hydrogen embrittles a material, the safety of welded components with hydrogen is always a critical issue. Weld heat input causes additional changes in the microstructure like grain growth or partial dissolution of precipitates and many more. All these things influence the mechanical properties and also represent hydrogen traps. These traps decrease the hydrogen diffusion compared to the ideal lattice. The result can be so-called delayed hydrogen assisted cracking (HAC) of the weld joint due to the significantly decreased diffusivity by trapped hydrogen. This is often an underestimated risk as those cracks can appear in the weld joint even after some days! It is essential to know about hydrogen ingress during welding and the microstructure specific hydrogen diffusion. Both are depended on weld parameter influence and the chemical composition of the base material and weld metal. For that purpose, gas analytic methods like solid-state carrier gas hot extraction (CGHE) are useful tools to: (1) identify detrimental hydrogen concentrations from weld joints, (2) binding energies from hydrogen traps by thermal desorption analysis or (3) high-temperature diffusion coefficients. Those values are extremely important for welding practice in terms of recommendations on realistic hydrogen removal heat treatment (HRHT) after welding. Considering the increasing use of “digital” experiments, the data is also needed for reliable numerical simulations of HAC process or HRHT-effectiveness. The present contribution gives an overview on the influence of hydrogen on weld joints, the necessity, methods and standards for hydrogen determination (CGHE) with the aim of fabrication of safe welded and crack-free components. [1] R. A. Oriani (1987), Corrosion 43(7):390-397. doi: 10.5006/1.3583875 T2 - 20. Tagung Festkörperanalyse - FKA20 CY - Vienna, Austria DA - 01.07.2019 KW - Hydrogen KW - Welding KW - Gas analytic PY - 2019 AN - OPUS4-48402 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Processing and application properties of multiple principal element alloys (MPEA) N2 - The presentation gives an overview of BAM's activities on processing influences and application properties of MPEAs in the form of joined and machined high and medium entropy alloys (CoCrFeMnNi and CoCrNi). In the case of welding, the focus is on defect-free welded joints with sufficient mechanical properties. In the case of machining, the focus is on the possible influence on the surface quality of the materials through adequate milling parameters. In addition, the hydrogen absorption and diffusion properties as well as the electrochemical corrosion behavior are fundamentally examined. T2 - FAU-Department Werkstoffwissenschaften, Seminar: Aktuelle Probleme der Werkstoffwissenschaften CY - Erlangen, Germany DA - 25.04.2024 KW - Welding KW - Application properties KW - Machining KW - High-entropy alloy KW - Hydrogen PY - 2024 AN - OPUS4-59975 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael A1 - Kaiser, Sebastian T1 - Repair welding of pressurized in-service hydrogen pipelines: A review on current challenges and strategies N2 - As energy carrier of the future, green hydrogen can make a decisive contribution to a sustainable energy supply. In Europe concrete plans for a hydrogen pipeline grid already exist, as the so called “European Hydrogen backbone”. As building a completely new pipeline grid is economically not justifiable, a dual-way strategy of repurposing natural gas (NG) pipelines and newly built pipelines is intended. Long distance pipeline grids require regular maintenance and repairs. In that conection, for natural gas (NG) pipelines in-service welding is state of the art. Concepts such as hot-tapping (drilling into pressurized pipelines) and “stoppling” (sealing off pipeline sections after installing bypasses or pressure relieves) allow the repair of damaged pipeline sections or the installation of new branches without shutting the pipeline down. The EIGA 121/14 guideline already pointed out in 2014 that “a hydrogen hot-tap shall not be considered a routine procedure”. This shows that the determination of the transferability of these repair concepts to hydrogen pipelines is of utmost importance. Due to the degrading effects of hydrogen on mechanical proper-ties, commonly referred to as “hydrogen embrittlement” it is necessary to understand and investigate the occurring effects. In the special case of repair welding on in-service hydrogen pipelines an increased hydro-gen uptake due to a large heat input and microstructural changes in the material needs to be considered. For this reason, this paper gives an overview on existing weld repair concepts and its risks and limitations in terms of hydrogen absorption and possible embrittlement effects when transferred to hydrogen pipelines. The complexity lies in a large variety of materials (low alloyed steels), pipeline diameters and corresponding welded joints. The material compatibility of materials in used (repurposed NG-pipelines) and new condition must be investigated. Particularly for repurposed/used pipelines the effect of a pre-matured/corroded inner surface and sometimes insufficient documentation of the material “history” needs to be considered. An overview on ongoing and completed R&D-projects with respect to repair concepts for hydrogen pipelines and hydrogen effects on pipeline materials is given. T2 - 77th IIW Annual Assembly and International Conference, Meeting of Commission XI "Pressure Vessels and Piping" CY - Ixia, Rhodes, Greece DA - 07.07.2024 KW - Hydrogen KW - Repair welding KW - Pipelines KW - Study PY - 2024 AN - OPUS4-60673 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael A1 - Kannengießer, Thomas T1 - Call for interested people to contribute to series of comprehensive papers on welding and joining of components for sustainable energy systems N2 - Joining and welding technologies are of high importance for the manufacturing of components and parts used in sustainable energy generation, conversion, and transport. In that connection, offshore and on-shore installed wind turbines are of high interest for the generation of electrical energy as well as photo-voltaic systems (solar cells). The electricity can be either directly transported or conversed via power-to-gas e.g., to hydrogen. In that scope, electrolyzer up to MW-range are of interest as well as the conver-sion back to electricity via fuel cells. In addition, hydrogen is a key element of the decarburization of in-dustries as well as the mobility sector encompassing sea, air and land transportation driven by hydrogen or its derivates. Well-known examples cover the direct reduction of iron ore to replace the conventional blast furnace process up to gas turbines or fuel cells for home-end use. All mentioned technologies re-quire reliable components, which are to a high extend dependent on joining and especially welding pro-cessing of materials. Especially, the (petro-) chemical industry has many years of experience with both materials used in hydrogen applications. The challenge is e.g., the transition to mass production of sys-tem components of electrolyzers/fuel cells and for distribution grids. At this point, the scalability of cur-rently applied joining processes often limits the economic efficiency, whereas especially laser welding or additive manufacturing will be of high interest. In that connection, it is very important to provide answers by joint research of universities, institutes, and industrial companies. Very often, solutions are already available and “just” have to be investigated and adapted for the new application, like repair welding of NG pipelines. For that reason, we want to set up a series of comprehensive papers with the aforementioned title. The idea is to get an in-depth but manageable overview of the importance of joining technologies in sustaina-ble energy generation, conversion, and transport encompassing current processes, limitations, and fur-ther perspectives. In that connection, the additive manufacturing is gaining more and more attention. If applicable, current challenges in the adaption or creation of new standards/regulations shall be addressed. T2 - IIW Intermediate Meeting, Com. II-A CY - Incheon, Republic of Korea DA - 12.03.2024 KW - Hydrogen KW - Welding KW - Comprehensive study KW - Component manufatcturing KW - Additive manufacturing PY - 2024 AN - OPUS4-59676 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael A1 - Kannengießer, Thomas T1 - Update on "Call for interested people to contribute to series of comprehensive papers on welding and joining of components for sustainable energy systems" N2 - Based on the initial call in March 2024, an update time-frame is introduced on the working plan for a comprehensive review paper series on joining and welding technologies for the manufacturing of components and parts used in sustainable energy generation, conversion, and transport with focus on hydrogen and wind energy. T2 - 77th IIW Annual Assembly and International Conference, Meeting of Commission II-A CY - Ixia, Rhodes, Greece DA - 07.07.2024 KW - Review paper KW - Research study KW - Hydrogen KW - Joining KW - Welding PY - 2024 AN - OPUS4-60674 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael A1 - Masoud Nia, Niloufar A1 - Nietzke, Jonathen A1 - Kannengiesser, Thomas T1 - Ti and Nb microalloying of HSLA steels and its effect on hydrogen diffusion and trapping N2 - Fine-grain, high-strength, low-alloy (HSLA) structural steels with yield strengths > 600 MPa are now the state of the art in construction applications such as mobile cranes and civil engineering. HSLA grades derive their strength from a combination of specific heat treatment and the underlying chemical composition. In this context, Ti or Nb are essential to obtain a fine-grained microstructure as well as the necessary carbides or nitrides for precipitation strengthening. In this context, the specific effect of Ti or Nb-rich compounds on hydrogen trapping and diffusion is well known for special laboratory cast alloys, but unknown for realistic steel compositions. For this reason, a series of S690Q-based alloys were synthesized, close to a real steel composition, but with well controlled Ti or Nb additions in different amounts. Specimens were obtained from these alloys by electrochemical discharge machining (EDM). The specimens were tested using the well-established electrochemical permeation technique. From the experimental results, the hydrogen diffusion coefficients and the analytical subsurface hydrogen concentration were calculated. In addition, the hydrogen trapping behavior at elevated temperatures was interpreted by thermal desorption analysis (TDA) using different heating rates of hydrogen charged samples. The results showed that in contrast to metallurgically "pure" laboratory cast alloys, realistic chemical compositions were similar in their hydrogen trapping behavior, despite some small differences. All investigated steel grades exhibited shallow and reversible hydrogen trapping, regardless of their chemical composition. Of course, the experiments only allowed the calculation of effective diffusion coefficients and trapping energies, which represent an average of the entire microstructure. Nevertheless, HSLA steels are typically joined by arc welding, which includes the risk of delayed hydrogen assisted cracking. From the point of view of welding practice, however, a more or less identical hydrogen diffusion behavior means that no special "metallurgically specific", justifiable measures need to be considered, despite the well-established processes such as "soaking" or dehydrogenation heat treatment. T2 - MPAC 2025 CY - Stuttgart, Germany DA - 06.10.2025 KW - HACC KW - Hydrogen KW - HSLA PY - 2025 AN - OPUS4-64337 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Richter, Tim T1 - Characterization of Hydrogen Diffusion in a Thick-walled Submerged Arc Multi-Layer Weld Joint N2 - The energy production of the future will be dominated by CO2-emission free techniques like wind turbines and become essential in scope of the planned hydrogen economy. As onshore installation capacity is limited, the in-crease of the number of offshore wind turbines (OWT) is a major goal. In that connection, the OWTs continuously increase in size and weight and demand adequate foundations concepts like monopiles or tripods. These compo-nents are typically manufactured from welded mild steel plates with thickness up to 200 mm. The predominant welding technique is submerged arc welding (SAW) with up to five wires. In accordance with the standards, the occurrence of delayed hydrogen assisted cracking is anticipated by either a hydrogen removal heat treatment (HRHT) or a so-called minimum waiting time (MWT) before non-destructive testing (NDT) of the respective weld joint is allowed. The reason for the MWT is the necessary time for the hydrogen diffusion at ambient temperature due the high plate thickness. Both the effectiveness of a HRHT at elevated temperatures or the MWT at ambient temperature can be estimated by calculation of the diffusion time. This time depends on reliable hydrogen diffu-sion coefficients and these are rare in literature. For that reason, this study presents the hydrogen diffusion coef-ficients obtained from a multi-layer SAW joint of an offshore steel grade. Two different experimental techniques were used to identify the respective diffusion behavior: (1) hydrogen desorption experiments with a carrier gas hot extraction analyzer at elevated temperatures for the characterization of a HRHT and (2) the electrochemical permeation technique at ambient temperature for the characterization of an MWT. From both experiments, the respective diffusion coefficients were calculated. The obtained DCs are different from those reported in literature, i.e., the duration or applicability of a HRHT or MWT must be critically discussed. T2 - European Congress and Exhibition on Advanced Materials and Process - Euromat 2021 CY - Online meeting DA - 13.09.2021 KW - Welding KW - Offshore KW - Wind turbine KW - Hydrogen KW - Cracking PY - 2021 AN - OPUS4-53296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scarponi, Giordano T1 - Numerical Simulation Of Cryogenic Liquid Hydrogen Tanks With Multilayer Insulation Exposed to Fire N2 - In the ongoing energy transition, hydrogen has emerged as a promising alternative energy carrier with a reduced environmental impact. Among the possible solutions to store hydrogen onboard vehicles, cryogenic tanks equipped with multilayer insulation (MLI) appear to be one of the most effective in ensuring high volumetric energy density. MLI systems consist of several layers of low-emissivity material (radiative layers), typically aluminum or aluminum-coated polyester, interleaved with low thermal conductivity spacers to avoid direct contact between the radiative layers. In cryogenic tank applications, these are enclosed within the vessel double-walled shell, working under high-vacuum conditions. Among the insulation systems available nowadays, MLI-based ones have the smallest volume requirements and the lowest weight. Thanks to these features, MLI appears as the preferable choice in sectors where space and weight constraints play a crucial role (e.g., in the transportation sector). The widespread deployment of LH2 new technologies poses also challenging questions related to the hazardous properties of hydrogen. The accidental loss of integrity of cryogenic LH2 tanks might lead to extremely dangerous phenomena, such as Boiling Liquid Expanding Vapour Explosions (BLEVE), Fireball, and Rapid Phase Transition (RPT). One potential scenario that could give rise to this situation is exposure to an external heat source such as a fire triggered by a road accident. Real-scale fire test results suggest that the insulation performance of MLI systems may undergo severe degradation when these are subjected to high temperatures, leaving the tank almost unprotected and leading to failure in a relatively short time. In this framework, the availability of models able to simulate the tank response to fire exposure is crucial to ensure a safe design and support emergency response planning. Several CFD and lumped models originally developed for pressurized and atmospheric tanks were extended to cryogenic vessels. However, these provide results in line with experimental data only if the insulation system's equivalent thermal conductivity is fine-adjusted to higher values with respect to normal operating conditions. These models do not integrate, in fact, the description of MLI thermal degradation as a result of fire exposure, which was demonstrated to play a crucial role in determining the response of the cryogenic liquid hydrogen tank. On the other hand, MLI heat transfer models currently available in the literature are suitable for normal operative conditions only and do not address the material behavior under fire exposure. This work presents an innovative lumped model to simulate the thermal response of MLI-insulated cryogenic hydrogen tanks in fire scenarios. In particular, the proposed approach enables the prediction of MLI loss of insulation performances due to fire-induced thermal degradation, overcoming the limitations of currently available models. The MLI degradation model is based on the well-established layer-by-layer approach and integrated with sub-models to estimate the material deterioration due to thermal load. Several sub-models were defined to account for different MLI materials. In particular, for polyester-based MLIs, the deterioration of each layer is defined by the apparent kinetic of thermal degradation retrieved from Thermo-Gravimetric-Analysis (TGA) tests. For aluminum-based MLI, each radiation layer is assumed to vanish when its temperature reaches the melting point of the material. The model was applied to several case studies addressing different types of MLI (i.e., both polyester-based and aluminum-based ones) and fire scenarios to assess the effect on the heating rate and pressure build-up of the tank lading. The analysis allowed for the performance comparison of the studied MLIs, providing valuable information to support the emergency management of accidental scenarios involving liquid-hydrogen cryogenic tanks. Moreover, the results obtained can be used to define mitigation measures to protect the integrity of cryogenic tanks equipped with MLI. T2 - Spring24+20thGCPS CY - New Orleans, Louisiana, USA DA - 24.03.2024 KW - Multilayer Insulation KW - Fire KW - Hydrogen KW - Liquefied Natural Gas KW - Insulation PY - 2024 AN - OPUS4-61078 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schaupp, Thomas T1 - Influence of heat control on hydrogen distribution in high-strength multi-layer welds with narrow groove N2 - High-strength low-alloyed (HSLA) steels with yield strength ≥ 690 MPa are gaining popularity in civil engineering and construction of heavy vehicles. With increasing yield strength, the susceptibility for degradation of the mechanical properties in presence of diffusible hydrogen, i.e. hydrogen-assisted cracking (HAC) generally increases. HAC is a result of the critical interaction of local microstructure, mechanical load and hydrogen concentration. In existing standards for welding of HSLA steels, recommendations like working temperatures and dehydrogenation heat treatment (DHT) are given to limit the amount of introduced hydrogen during welding. The recommendations are based on investigations with conventional arc welding processes. In the past decade, modern weld technologies were developed to enable welding of narrower weld seams with V-grooves of 30°, e.g. the modified spray arc process. In that connection, a reduced number of weld runs and weld volume are important technical and, hence, economic benefits. In the present study, the hydrogen distribution in S960QL multi-layer welds with thickness of 20 mm was analyzed. The influence of different weld seam opening angles, heat input, working temperature and DHT was investigated. The results show that weldments with narrow groove contained increased diffusible hydrogen amount. Hydrogen concentration has been reduced by decreasing both the heat input and working temperature. Hydrogen free weldments were only achieved via subsequent DHT after welding. Furthermore, hydrogen distribution was experimentally determined across the weld seam thickness in HSLA GMA welded multi-layer welds for the first time. T2 - 71st IIW Annual Assembly and International Conference: Commission II-A CY - Nusa Dua, Bali, Indonesia DA - 15.07.2018 KW - Hydrogen KW - GMAW KW - High-strength steels KW - Heat control KW - Heat treatment PY - 2018 AN - OPUS4-45622 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schaupp, Thomas T1 - Effect of weld penetration depth on hydrogen-assisted cracking of high-strength structural steels N2 - The need for steels with highest mechanical properties is a result of the increasing demands for energy and resource efficiency. In this context, high-strength structural (HSS) steels are used in machine, steel and crane construction with yield strength up to 960 MPa. However, welding of HSS steels requires profound knowledge of three factors in terms of avoidance of hydrogen-assisted cracking (HAC): the interaction of (1) microstructure, (2) local stress/strain and (3) local hydrogen concentration. In addition to the three main factors, the used weld-arc process is also important for the performance of the welded joint, especially when using modern arc variants. In the past, the conventional transitional arc process (Conv. A) was mainly used for welding of HSS grades. In the past decade, the so-called modified spray arc process (Mod. SA) has been used increasingly for welding production. This modified process enables reduced seam opening angles with increased deposition rates compared to the conventional process. Economic benefits of using this arc type are: a reduced number of necessary weld beads and a lower weld seam volume, which result in decreased total welding time and costs. Nonetheless, investigations on a high-strength S960QL showed significantly higher hydrogen concentrations in the weld metal at a reduced seam opening angle with Mod. SA. This indicates an increased susceptibility of the welded component to HAC. Hence, existing recommendations on HAC-avoidance cannot be transferred directly to the Mod. SA-process. In the present study, the susceptibility to HAC of the HSS steel S960QL with same type of filler material was investigated. For that purpose, both Conv. A and Mod. SA were used with same heat input at different deposition rates. For assessment of the HAC susceptibility, the externally loaded implant test was used. Both conducted test series with Conv. A and Mod. SA showed similar crack critical stress of about 280 MPa. Below this value, no delayed fracture appeared. The welds with Mod. SA showed higher hydrogen concentrations. The fracture occurred in the heat-affected zone (HAZ) or in the weld metal (WM). However, the test series with Mod. SA showed a significant extension of the time to failure of several hours compared to tests carried out with Conv. A. T2 - 72nd IIW Annual Assembly and International Conference: Commission II-A CY - Bratislava, Slovakia DA - 07.07.2019 KW - Hydrogen KW - Implant test KW - High-strength steels KW - Fractography PY - 2019 AN - OPUS4-48462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlegel, Moritz-Caspar T1 - Nano-porous Materials - Introduction into Metal-organic Frameworks N2 - Metallic organic frameworks are the materials stirring great interest by their large variety of structure types and chemical composition as well as low density and very high surface area, which are desirable properties for gas storage such as for hydrogen, methane or carbon dioxide. Using different so called secondary building units offer an opportunity to form tunable structures with channels of various geometry and allow in this way to study the absorption of the molecular hydrogen, methane or carbon dioxid in the systematic way. T2 - Neutron Scattering Application to Hydrogen Storage Materials CY - Berlin, Germany DA - 07.08.2017 KW - MOFs KW - Hydrogen KW - Crystallography PY - 2017 AN - OPUS4-41285 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schulze, Uwe T1 - Measurement of permeation of hydrogen on hoses according to ISO 3821 N2 - The subject of permeation of hoses according to ISO 3821 for hydrogen was discussed for a long time in ISO/TC 44/SC 8. The reason is a considerable leakage of hydrogen diffused into the hose material over the end face of the hose. Because of this unsolved, safety-related problem of hoses sold on the market, measurements should be carried out in order to be able to better assess the problem. BAM has declared its attendance to provide a required fast solution to this issue. T2 - Meeting of the committee ISO/TC 44/SC 8 "Equipment for gas welding, cutting and allied processes" CY - Genoa, Italy DA - 08.11.2023 KW - Permeation KW - Hoses KW - Hydrogen KW - Leakage KW - ISO 3821 PY - 2023 VL - 2023 AN - OPUS4-59375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Safety of Prestressing Steels N2 - This talk reports the findings of the WIPANO "Knowledge and Technology Transfer via Patents and Standards" research project "Safety of Prestressing Steels," founded by the German Ministry of Economic Affairs and Climate Action (BMWK). A new test method for assessing the susceptibility of prestressing steels to hydrogen-induced stress corrosion cracking (SCC) is presented, which serves the demands of a lower scattering compared with the present standard. Moreover, the ability to differentiate between high susceptible and low susceptible prestressed wires is possible, modifying the method by hydrogen charging and surface preparation. T2 - Konferenz EUROCORR 2022 CY - Berlin, Germany DA - 28.08.2022 KW - ISO 15630-3 KW - Stress Corrosion Cracking KW - Prestressing Steels KW - Hydrogen KW - Constant Load Test PY - 2022 AN - OPUS4-55661 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Committee Meeting to WIPANO "Safety of Prestressing Steels" N2 - A conclusion on the WIPANO research project "Safety of Prestressing Steel" was presented in the final committee meeting at the end of the project. The project's exciting findings and recommendations for a new method were discussed with the audience of national and international stakeholders of the prestressing steel industry and representatives of inspection bodies and standardization. T2 - Committee Meeting to WIPANO research Project CY - Online meeting DA - 29.09.2022 KW - ISO 15630-3 KW - Prestressing Steels KW - Hydrogen-induced Stress Corrosion Cracking KW - Hydrogen PY - 2022 AN - OPUS4-56101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Souza Filho, I. A1 - Adam, Christian T1 - Fundamentals of the hydrogen plasma reduction of iron ores N2 - Hydrogen plasma treatment of iron ores or iron oxide containing wastes can be an efficient option to produce green iron e.g. for steel production. This way iron oxide is reduced to metallic iron in the liquid form by the highly reactive species that are formed in a hydrogen plasma. Hydrogen plasma can be used at the same time to remove undesired gangue elements. The presentation shows the experimental setup, shows first results of iron ore reduction by hydrogen plasma and gives an outlook for industrial application of the technology. T2 - European Academic Symposium on EAF steelmaking (EASES 2023) CY - Oulu, Finland DA - 05.06.2023 KW - Hydrogen KW - Plasma KW - Reduction PY - 2023 AN - OPUS4-57626 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Sliding behaviour of polymer materials in hydrogen N2 - This lecture deals with the sliding behaviour of polymer materials in hydrogen environment. After a short introduction of the hydrogen activities at BAM, the tribological performances of polymer materials in gaseous hydrogen are presented and compared with air and vacuum environment. The second part focusses on the influence of the counterface materials in hydrogen. Finally, the last section is dedicated to experiments liquid hydrogen. T2 - Invited lecture, TRIBOS+ program at Lulea University of Technology CY - Lulea, Sweden DA - 30.06.2021 KW - Polymers KW - Hydrogen KW - Friction KW - Wear PY - 2021 AN - OPUS4-53708 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Effect of hydrogen pressure on the fretting behavior of elastomers N2 - In this study, the fretting behavior of several elastomer materials against 316L were evaluated in air and hydrogen environment up to 10 MPa. Furthermore, aging experiments were conducted for 7 days under static conditions in 100 MPa hydrogen and the physical and mechanical properties of the rubber materials were examined before and after hydrogen exposure. Fretting tests revealed that the wear of these compounds is significantly affected by the hydrogen environment compared to air, especially with NBR grades. After aging experiment, the friction response of HNBR grades is characterized by increased adhesion due to elastic deformation, leading to partial slip. T2 - ITC 2023: 9th International Tribology Conference 2023 CY - Fukuoka, Japan DA - 26.09.2023 KW - Hydrogen KW - Fretting KW - Elastomers PY - 2023 AN - OPUS4-61962 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Fretting behavior of elastomer materials in hydrogen N2 - This presentation deals with the fretting wear behavior of elastomer materials (two types of cross-linked hydrogenated acrylonitrile butadiene rubbers) against 316L steel ball in hydrogen environment. Furthermore, aging experiments were conducted for 7 days under static conditions in 100 MPa hydrogen. Fretting tests revealed the wear of the polymer decreases with increasing hydrogen pressure. After high pressure hydrogen exposure, the fretting process is characterized by increased adhesion due to elastic deformation, leading to partial slip. T2 - 63rd German Tribology Conference 2022 CY - Göttingen, Germany DA - 26.09.2022 KW - Fretting KW - Rubbers KW - Hydrogen PY - 2022 AN - OPUS4-62082 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - On the way to sustainable and hydrogen compatible sealing materials N2 - In this contribution, the sliding performance of newly formulated polymer materials with improved sustainability are investigated and compared with conventional materials. Tribological tests were performed in hydrogen at ambient temperature as well as cryogenic medium. The samples were arranged in a pin-on-disk configuration with a flat pin sliding against a rotating austenitic steel disk. The friction and wear mechanisms are described and discussed by means of surface analyses. T2 - PolyTrib 2024 CY - Portoroz, Slowenia DA - 03.10.2024 KW - High-performance polymers KW - Sliding wear KW - Hydrogen KW - Cryogenic PY - 2024 AN - OPUS4-61419 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Fretting wear of elastomer materials in hydrogen N2 - This paper presents an experimental study on the fretting wear behavior of two types of cross-linked hydrogenated acrylonitrile butadiene rubbers against 316L steel ball in hydrogen environment. Furthermore, aging experiments were conducted for 7 days under static conditions in 100 MPa hydrogen. The influences of hydrogen pressure as well as the aging exposure on the fretting behavior are discussed by means of surface analyses and well as material properties. T2 - WHEC-2022, 23rd World Hydrogen Energy Conference CY - Istanbul, Turkey DA - 26.06.2022 KW - Rubbers KW - Hydrogen KW - Fretting PY - 2022 AN - OPUS4-62086 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Polymer tribology in cryogenic hydrogen N2 - In this presentation, an overview of polymer tribology in cryogenic hydrogen is given along comparison with other environments. T2 - Hydrogenius Symposium 2024 CY - Kyushu University Ito Campus, Japan DA - 12.09.2024 KW - Hydrogen KW - Friction KW - Wear KW - Polymer materials KW - Cryogenic PY - 2024 AN - OPUS4-61426 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Environmental effects on the sliding behaviour of polymer composites N2 - The tribological behaviour of polyetheretherketone (PEEK) and polyimide (PI) composites was investigated in air, vacuum and hydrogen environments. Polymers were filled with graphite, submicron particles or carbon nano-tubes. Experiments reveal that hydrogen environment has a major influence on both polymer structure and fillers during sliding. The sliding behaviour of these polymer composites is much improved in hydrogen compared to air. In particular, graphite and nano-particles have a remarkable effect on friction and wear, respectively. T2 - BAM Kolloquium Abteilung Werkstofftechnik CY - Berlin, Germany DA - 09.06.2016 KW - Sliding friction KW - Polymer composites KW - Hydrogen KW - Vacuum PY - 2016 AN - OPUS4-38139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Tribology of polymers materials in hydrogen N2 - The paper deals with the tribological properties of polymers in hydrogen gas at ambient temperature as well as in liquid hydrogen (-253°C). The influence of hydrogen is discussed in relation to compositions and triboreactions. T2 - Hydrogenius and I2CNER Tribology Symposium CY - Fukuoka, Japan DA - 02.04.2016 KW - Polymers KW - Hydrogen KW - Tribology PY - 2016 AN - OPUS4-38138 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Effect of high-pressure hydrogen environment on the physical and mechanical properties of elastomers N2 - This presentation deals with the exposure of HNBR rubbers to high pressure hydrogen (100 MPa) at 120 °C for 7 and 21 days under static conditions followed by characterization of their physical and mechanical properties.The core areas include swelling, rapid gas decompression, dynamic mechanical analysis (DMA), tensile strength and compression set properties. This study will assist in expanding the knowledge base of elastomer compatibility with hydrogen and therefore contribute significantly to the selection and development of polymer materials deploying hydrogen as a future energy carrier. T2 - EHEC European Hydrogen Energy Conferecne 2022 CY - Madrid, Spain DA - 18.05.2022 KW - Rubbers KW - Hydrogen KW - Characterization PY - 2022 AN - OPUS4-62084 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Influence of the counterface on the sliding behavior of polymer materials in hydrogen N2 - This presentation deals with the influence of the counterface materials on the sliding behaviour of some polymer materials in hydrogen. Polyimide (PI), polyetheretherketone (PEEK) and Polytetrafluoroethylene (PTFE) materials were investigated against hardened 52100 martensitic bearing steel and 304 austenitic stainless steel with similar roughness (Ra = 0.2 μm). Results indicate that the friction and wear of PI and PEEK materials depend on the counterface material. This effect wasn’t observed for PTFE composites. While the tribological performance of polyimide is better against 52100 in hydrogen, improved sliding behaviour of PEEK materials is observed with 304 counterface, particularly at higher sliding speed. Surface analyses of the transfer film reveal that the influence of the counterface is primarily related to the chemical nature of the steel for PI and to the thermal conductivity of the disc for PEEK materials. T2 - Hydrogenius & I2CNER Tribology Symposium CY - Online meeting DA - 29.01.2021 KW - Polymers KW - Hydrogen KW - Counterface KW - Friction KW - Wear PY - 2021 AN - OPUS4-52093 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Polymer materials in hydrogen N2 - This presentation provides an overview of the applications and challenges related to polymer materials in hydrogen. The effects of hydrogen on polymers are described and test methods to evaluate the interactions between polymers and hydrogen are presented along with case studies. T2 - Masterstudiengang Wasserstofftechnologien DIU CY - Online meeting DA - 25.08.2023 KW - Hydrogen KW - Polymers PY - 2023 AN - OPUS4-61964 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Tribology of polymeric materials in gaseous and liquid hydrogen N2 - This presentation gives an overview of the tribological behaviour of polymeric materials in gaseous and luquid hydrogen. T2 - HYDROGENIUS-BAM Joint Hydrogen Symposium CY - Online meeting DA - 06.07.2021 KW - Polymers KW - Hydrogen KW - Friction KW - Wear PY - 2021 AN - OPUS4-53701 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Benchmarking of polymer materials for tribological applications in hydrogen N2 - The focus of this study is to evaluate of hydrogen on the friction and wear behavior of a wide range of polymer materials. Thereby, the tribological performance of filled and unfilled polymers from different suppliers were compared at room temperature in air and hydrogen gas (H2) as well as in liquid hydrogen at -253°C (LH2). T2 - 62. Tribologie-Fachtagung der Gesellschaft für Tribologie e. V. CY - Online meeting DA - 27.09.2021 KW - Polymers KW - Hydrogen KW - Friction KW - Wear PY - 2021 AN - OPUS4-53700 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Friction and wear characteristics of polymers in gaseous and liquid hydrogen N2 - The tribological characteristics of pure and graphite filled polymers were investigated in gaseous hydrogen at ambient temperatures and in LH2 at -253°C. It could be shown that the tribological properties of PI and PEEK materials is related to the formation of a transfer film. The influence of both hydrogen and cryogenic temperatures will be discussed in the presentation. T2 - 21th International Colloquium Tribology CY - Stuttgart/Ostfildern, Germany DA - 09.01.2018 KW - Friction KW - Wear KW - Hydrogen KW - PEEK PY - 2018 AN - OPUS4-43902 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Comparison of the sliding behaviour of several polymers in hydrogen N2 - The work presented here deals with the friction and wear behaviour of polymer materials in hydrogen. Commercially available grades of PEEK, PA, PPA, PAI, PI and PBI were investigated at room temperature in air and hydrogen gas (H2) as well as in liquid hydrogen at - 253°C (LH2). T2 - 7th World Tribology Congress, WTC 2022 CY - Lyon, France DA - 10.07.2022 KW - Friction KW - Wear KW - Polymers KW - Hydrogen KW - Cryogenic PY - 2022 AN - OPUS4-62087 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Friction and wear characteristics of polymers in gaseous and liquid hydrogen N2 - The presentation deals with the investigation of polymer composites for their suitability for friction systems in gaseous and liquid hydrogen. T2 - 59. Tribologie-Fachtagung CY - Goettingen, Germany DA - 24.09.2018 KW - Friction KW - Wear KW - Polymer composites KW - Hydrogen KW - Cryogenic temperature PY - 2018 AN - OPUS4-46184 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Tribology of polymer materials in cryogenic hydrogen and methane N2 - The development of hydrogen technologies is a key strategy to reduce greenhouse gas emission worldwide. Power-to-Gas is a challenging solution, in which hydrogen and methane can be used in mobility, industry, heat supply and electriity generation applications. This presentation deals with the tribological behaviour of polymer materials in hydrogen and methane, both in gas and in liquid form. T2 - 2018 HYDROGENIUS & I2CNER Tribology Symposium CY - Fukuoka, Japan DA - 02.02.2018 KW - Hydrogen KW - Methane KW - Sliding friction KW - Polymers KW - Cryogenic temperature PY - 2018 AN - OPUS4-44483 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Tribology of polymer materials in hydrogen N2 - The polymer chemical structure of the polyimide has a major influence on the tribological behaviour. The addition of graphite in PI2 has a beneficial effect in hydrogen on the friction and wear. The low friction of graphite is associated with a lubricant film in hydrogen. The influence of hydrogen on graphite is more effective than humidity. CNTs have a similar effect to that of graphite in PEEK composites. TiO2 particles improve significantly the wear rate both in vacuum and hydrogen environment. In LH2 friction and wear decrease for unfilled polymers. Friction of graphite filled composites increases slightly and wear rate is stable. T2 - 10. International Hydrogen Energy Development Forum 2016 / 2016 HYDROGENIUS & I2CNER Tribology Symposium CY - Fukuoka, Japan DA - 04.02.2016 KW - Hydrogen KW - Tribology KW - Polymer materials KW - Cryogenic temperature KW - CNT KW - TiO2 KW - PEEK PY - 2016 AN - OPUS4-35641 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - An overview of tribology in gaseous Hydrogen N2 - In this presentation, an overview in gaseous hydrogen is given along with examples related to metal, coatings, polymers and rubbers materials. T2 - International Seminar, Hydrogen & Materials 2024 CY - Espoo, Finland DA - 06.06.2024 KW - Hydrogen KW - Friction KW - Wear KW - Materials PY - 2024 AN - OPUS4-61408 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Effect of hydrogen pressure on the fretting behavior of elastomers N2 - In this study, the fretting behavior of several elastomer materials against 316L were evaluated in air and hydrogen environment up to 10 MPa. Furthermore, aging experiments were conducted for 7 days under static conditions in 100 MPa hydrogen and the physical and mechanical properties of the rubber materials were examined before and after hydrogen exposure. Fretting tests revealed that the wear of these compounds is significantly affected by the hydrogen environment compared to air, especially with NBR grades. After aging experiment, the friction response of HNBR grades is characterized by increased adhesion due to elastic deformation, leading to partial slip. T2 - 4th Int. Conf. on Polymer Tribology, PolyTrib 2022 CY - Stockholm, Sweden DA - 05.12.2022 KW - Hydrogen KW - Fretting KW - Elastomers PY - 2022 AN - OPUS4-62006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Toward sustainable and hydrogen compatible sealing materials N2 - As sealing components, polymeric materials are used in a wide range of applications e.g. as O-rings and piston rings in high-pressure and/or cryogenic hydrogen. For these extreme demanding application, PTFE or PPS based materials are often used as high-performance polymer matrix. This project aims to provide a safe and sustainable sealing solutions for hydrogen applications. New materials with improved sustainability were investigated and compared with conventional grades. Tests were performed in hydrogen over a wide range of temperature and pressure (0.1 MPa to 40 MPa, and 100°C down to -150°C) at Kyushu University and BAM using a pin-on-disk apparatus in a continuous sliding motion. Polymer samples ran against 316L disk at 0.5 m/s and 3 MPa contact pressure. Based on the tribological results and surface analyses, promising candidates are suggested along with friction mechanisms in both high-pressure and low temperature hydrogen. T2 - STLE Meeting CY - Atlanta, Georgia, USA DA - 18.05.2025 KW - Hydrogen KW - Friction KW - Wear KW - Piston ring KW - Reciprocating seals PY - 2025 AN - OPUS4-63809 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Comparative evaluation of the sliding performance of polymers materials in gaseous and liquid hydrogen N2 - The focus of this study is to evaluate the influence of hydrogen on the friction and wear behavior of a wide range of commercially available polymer materials. Thereby, Filled and unfilled polymers from different suppliers were evaluated at room temperature in air and hydrogen gas (H2) as well as in liquid hydrogen at - 253°C (LH2). T2 - 2023 Hydrogenius & I2CNER Tribology Symposium CY - Fukuoka, Japan DA - 03.02.2023 KW - Hydrogen KW - Tribology KW - Cryogenic KW - LH2 KW - Polymers PY - 2023 AN - OPUS4-61961 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Sliding performance of polymer materials in hydrogen and methane N2 - In this talk, the sliding performance of polymer materials in hydrogen and methane are presented. The influence of the environmental conditions is discussed in terms of material composition, counterface, transfer film formation, and triboreactions. T2 - International Tribology Conference/ITC CY - Sendai, Japan DA - 17.09.2019 KW - Friction KW - Wear KW - Polymer composites KW - Hydrogen KW - Methane PY - 2019 AN - OPUS4-49148 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Géraldine T1 - Tribological behavior of polymeric materials in hydrogen N2 - In this talk, an overview of BAM research activities related to Hydrogen is given with a brief presentation of the Competence Center H2Safety@bam. The second part focuses on current projects dealing with the tribological behavior of polymeric materials in Hydrogen. In particular, results regarding the performances of PTFE -free and sustainable materials are given and promising candidates are suggested along with friction mechanisms. T2 - International Hydrogen Energy Development Forum & HYDROGENIUS SYMPOSIUM 2025 CY - Kyushu, Japan DA - 17.12.2025 KW - Hydrogen KW - Friction KW - Wear KW - PTFE-free KW - Sustainable material PY - 2025 AN - OPUS4-65364 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Error prevention, damage prevention, and safety management in hydrogen technologies N2 - This tutorial presents requirements and properties of sensor systems and shows application examples of these technologies for safety and process control for hydrogen technologies. Sensor systems are widely used in hydrogen technologies. The focus is on gas sensors as well as sensors for pressure, temperature, and gas flow. These systems are applied, among other things, for monitoring and control of operating conditions, indication of hazardous conditions and triggering of alarms. To integrate the error avoidance and loss prevention strategy into hydrogen technologies. This includes the implementation of preventive measures as elements of safety management to identify and eliminate potential sources of error. In addition, training should be specifically focused on avoiding errors and the safe use of hydrogen technologies. A well-thought-out strategy for error prevention makes a significant contribution to preventing accidents and increasing overall safety when using hydrogen. T2 - Sensor and Measurement Science International (SMSI) CY - Nuremberg, Germany DA - 06.05.2025 KW - Hydrogen KW - Safety Management KW - Gas Sensors KW - Performance Testing PY - 2025 AN - OPUS4-63280 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Sensors for safety and process control in hydrogen technologies N2 - This tutorial provides an overview of the utilization of sensor systems in hydrogen technologies. It discusses the necessary criteria and characteristics of sensor systems, and also demonstrates practical applications of these technologies in terms of safety and process control. Emphasis is placed on various types of sensors such as gas sensors, pressure sensors, temperature sensors, and gas flow sensors. These systems find application in monitoring and regulating operational parameters, detecting potentially dangerous situations, and activating alarm systems. T2 - Sensor and Measurement Science International - SMSI 2023 CY - Nuremberg, Germany DA - 08.05.2023 KW - H2Safety@BAM KW - SensRef KW - Hydrogen KW - Gas sensor KW - Functional safety KW - Uncertainty KW - QI-Digital PY - 2023 AN - OPUS4-57532 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Hydrogen sensing - Sensors for safety and process control in Hydrogentechnologies N2 - The success of this energy transition and the efficient utilization of green hydrogen as a pristine energy carrier hinge upon the cultivation of hydrogen readiness, swift market expansion, and the establishment of crucial value chains within national and European contexts. Paramount to these objectives are reliable quality and safety standards, essential for ensuring supply safety, environmental compatibility, and instilling confidence in these technologies. In the realm of safety management systems, gas sensors emerge as vital components for detecting hydrogen. This presentation delves into the imperative role of hydrogen systems, emphasizing their capability to monitor and control operations, issue warnings, signal hazardous conditions, and sound alarms. It explores the intricate landscape of functional safety considerations and addresses the challenges associated with measurement uncertainty in sensor testing. A diverse array of sensors catering to hydrogen, pressure, temperature, and flow are available, each contributing significantly to the safety and efficiency of hydrogen technologies. Applications are envisaged to adhere meticulously to quality infrastructural regulations, codes, and standards, ensuring seamless integration and operation within the broader hydrogen ecosystem. This discussion underscores the ubiquitous presence of sensor systems across various fields within hydrogen technologies, illustrating their multifaceted contributions to safety, reliability, and overall success in realizing the transformative potential of green hydrogen. T2 - Summer School 2023 Characterization of micro- and nano-materials at BTU Cottbus CY - Cottbus, Germany DA - 11.09.2023 KW - H2Safety@BAM KW - Hydrogen KW - Sensor KW - Gas detection KW - Process control KW - Safety KW - Sensor testing PY - 2023 AN - OPUS4-59227 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Hydrogen sensing - Sensors for safety and process control in Hydrogentechnologies N2 - The success of this energy transition and the efficient utilization of green hydrogen as a pristine energy carrier hinge upon the cultivation of hydrogen readiness, swift market expansion, and the establishment of crucial value chains within national and European contexts. Paramount to these objectives are reliable quality and safety standards, essential for ensuring supply safety, environmental compatibility, and instilling confidence in these technologies. In the realm of safety management systems, gas sensors emerge as vital components for detecting hydrogen. This presentation delves into the imperative role of hydrogen systems, emphasizing their capability to monitor and control operations, issue warnings, signal hazardous conditions, and sound alarms. It explores the intricate landscape of functional safety considerations and addresses the challenges associated with measurement uncertainty in sensor testing. A diverse array of sensors catering to hydrogen, pressure, temperature, and flow are available, each contributing significantly to the safety and efficiency of hydrogen technologies. Applications are envisaged to adhere meticulously to quality infrastructural regulations, codes, and standards, ensuring seamless integration and operation within the broader hydrogen ecosystem. This discussion underscores the ubiquitous presence of sensor systems across various fields within hydrogen technologies, illustrating their multifaceted contributions to safety, reliability, and overall success in realizing the transformative potential of green hydrogen. T2 - Joint European Summer School 2023 on Fuel Cell, Electrolyser, and Battery Technologies CY - Vravrona, Greece DA - 17.09.2023 KW - H2Safety@BAM KW - SensRef KW - Hydrogen KW - KICstartH2 KW - Gas detection KW - Sensor testing KW - Hydrogen gas sensor PY - 2023 AN - OPUS4-59228 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Error Prevention, Damage Prevention, and Safety Management in Hydrogen Technologies N2 - In order to integrate the error prevention and damage prevention strategy into hydrogen technologies, it is important to proactively look out for potential weaknesses in the systems and processes. This includes the implementation of preventive measures as elements of safety management in order to identify and eliminate potential sources of error. In addition, training should be specifically focussed on avoiding errors and the safe use of hydrogen technologies. The principial approach of a gas sensor testing laboratory shows how to ensure reliable results, it is advisable to conduct sensor testing under controlled conditions, focusing on identifying specific properties and quantifying performance criteria. A well thought-out strategy for error prevention makes a significant contribution to preventing accidents and increasing overall safety when using hydrogen. T2 - 5th Germany-Korea Hydrogen Conference CY - Halle (Saale), Germany DA - 22.10.2024 KW - Hydrogen KW - Safety KW - Safety Management KW - Error Prevention KW - Reference Procedure PY - 2024 AN - OPUS4-62563 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Introduction of H2Safety@BAM N2 - This contribution for the Open Forum of the 8th HSN Symposium introduces the SensRef activities of the Competence Centre H2Safety@BAM. T2 - 8. HSN-Symposium - HybridSensorNet e. V. CY - Online meeting DA - 11.11.2021 KW - H2Safety@BAM KW - SensRef KW - Hydrogen PY - 2021 AN - OPUS4-54137 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Hydrogen Sensing - Sensors for Safety and Process Control in Hydrogen Technologies N2 - The success of this energy transition and the efficient utilization of green hydrogen as a pristine energy carrier hinge upon the cultivation of hydrogen readiness, swift market expansion, and the establishment of crucial value chains within national and European contexts. Paramount to these objectives are reliable quality and safety standards, essential for ensuring supply safety, environmental compatibility, and instilling confidence in these technologies. In the realm of safety management systems, gas sensors emerge as vital components for detecting hydrogen. This presentation delves into the imperative role of hydrogen systems, emphasizing their capability to monitor and control operations, issue warnings, signal hazardous conditions, and sound alarms. It explores the intricate landscape of functional safety considerations and addresses the challenges associated with measurement uncertainty in sensor testing. A diverse array of sensors catering to hydrogen, pressure, temperature, and flow are available, each contributing significantly to the safety and efficiency of hydrogen technologies. Applications are envisaged to adhere meticulously to quality infrastructural regulations, codes, and standards, ensuring seamless integration and operation within the broader hydrogen ecosystem. This discussion underscores the ubiquitous presence of sensor systems across various fields within hydrogen technologies, illustrating their multifaceted contributions to safety, reliability, and overall success in realizing the transformative potential of green hydrogen. T2 - Joint European Summer School JESS 2024 CY - Vravrona, Greece DA - 16.09.2024 KW - H2Safety@BAM KW - Hydrogen KW - Sensor KW - Sensor technology KW - Safety KW - Process control PY - 2024 AN - OPUS4-61677 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo A1 - Bayat, Mehmet E. T1 - Measurement and Testing Methods for Sensors in Hydrogen Technologies N2 - To ensure accurate results, it is advisable to conduct sensor testing under controlled conditions, focusing on identifying specific properties and quantifying performance criteria. The necessity of these evaluations lies in determining if a potentially beneficial sensor is a good fit for a specific application. Devices are typically factory-calibrated in according to ISO/IEC 17025, followed by testing/validation prior to intended use. Subsequent inspections/validations performance tests and long-term stability should be repeated in appropriate intervals. We present the testing and calibration validation of a hydrogen sensor intended for safety applications, using dynamic dilution of hydrogen into clean, dry air. • Sensor testing for the determination of non-explosive gas mixture composition, response time and characteristic curves of gas sensors, gas measuring devices. • Hydrogen mole fraction: 100 μmol/mol to > 4.0 cmol/mol – (approximately equal to 0.1 Vol-% to > 4.0 Vol-%) • Humidity: frost-point temperatures in the range of -85 °C to 15 °C (equal to 0.2 μmol/mol to 17000 μmol/mol humidity mole fraction) at ambient pressure • Sensor output provided directly in hydrogen volume percent, as defined by the factory calibration. The results obtained from the device under test demonstrate the effectiveness of the evaluated gas sensor in detecting and quantifying hydrogen. Its responses to different amounts of hydrogen in air and reliably returns to zero. To quantify the generated hydrogen mole fractions in situ and in operando, a process-GC-TCD-TCD system calibrated against our primary gas standards was used, ensuring the highest accuracy as a designated institute for primary gas standards. This procedure provides a foundation for modern and efficient quality assurance of gas sensors. T2 - 2025 IARIA Annual Congress on Frontiers in Science, Technology, Services, and Applications CY - Venice, Italy DA - 06.07.2025 KW - Hydrogen KW - Sensor KW - Quality KW - Validation KW - Data analysis KW - Reference procedure PY - 2025 AN - OPUS4-64047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Wolfgang T1 - Tof-SIMS imaging of Deuterium in DSS steel microstructures and data fusion with SEM topography data: Towards a better understanding of hydrogen assisted cracking in steel N2 - The use of duplex stainless steels (DSS) in energy related applications is well known. Nowadays, DSS steels become more favorable than austenitic steels due to the outstanding mechanical properties, the good corrosion resistance and the lower nickel content. However, the use of the duplex grade in acidic environments such as seawater often leads to severe degradation of the structural integrity of the steel by hydrogen-induced/assisted cracking (HAC) phenomena, which can eventually result in premature failure. Hydrogen assisted degradation and cracking of steels are active fields of research even though this topic is intensively studied for more than a century. A bottleneck is the analytical validation of the theoretical models proposed ion the literature at the sub-micron scale. Industrial and the research communities see a need for an accurate analytical method by which it is possible to image the distribution of hydrogen in the microstructure of a steels or and other alloys. Among the very few available methods hydrogen imaging methods, Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) has the principal capability for mapping of hydrogen in a steel’s microstructure. The combination of ToF-SIMS with multivariate data analysis (MVA), electron microscopy (SEM) and electron-backscattered diffraction (EBSD) is a powerful approach for providing chemical and structural information. The use of data fusion techniques has been shown recently to enhance the better understanding of the hydrogen induced degradation processes in in a DSS steel. T2 - The Scientific International Symposium on SIMS and Related Techniques Based on Ion-Solid Interactions (SISS19) CY - Kyoto, Japan DA - 11.5.17 KW - Hydrogen KW - DSS steel KW - ToF SIMS KW - SEM KW - EDX KW - EBSD KW - Data fusion PY - 2017 AN - OPUS4-40276 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Widjaja, Martinus Putra T1 - Impact damage evaluation of hydrogen composite pressure vessels by analysing computed tomography images N2 - The objective of this work is to find a method that describes the degree of damage from an impact experiment. This experiment was performed on Composite Pressure Vessels (CPV) in order to find the correlation of impact damage to the residual burst pressure. Computed Tomography (CT) approach was used to capture the before and after impact condition of the CPVs. The Wasserstein function was used to calculate how much the after impact image has differed from the original one. In the end, a good correlation was obtained to the residual burst pressure. The smaller the Wasserstein distance is, the higher the residual burst pressure would be and vice versa. T2 - HyFiSyn Conference CY - Online meeting DA - 15.09.2021 KW - Hydrogen KW - Composite pressure vessel KW - Carbon fibre KW - Burst test KW - Image analysis KW - Computed tomography (CT) PY - 2021 AN - OPUS4-53496 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -