TY - CONF A1 - Gluth, Gregor ED - Rogge, Andreas ED - Meng, Birgit T1 - Dauerhaftigkeit von Betonen auf Basis klimafreundlicher Bindemittel N2 - Aus Gründen des Klimaschutzes werden in den kommenden Jahren mehr Zemente mit verringertem Klinkerfaktor und alternative Bindemittel (klimafreundliche Bindemittel) zum Einsatz kommen. Für ihre sichere und zuverlässige Verwendung ist ein umfangreiches Verständnis der Einflüsse auf die Dauerhaftigkeit der aus ihnen hergestellten Betone notwendig. Der vorliegende Beitrag gibt einen kurzen Überblick über einige jüngere Entwicklungen und Forschungsergebnisse auf dem Gebiet. Der Fokus liegt auf Ergebnissen der Arbeiten von Technischen Komitees der RILEM sowie der EFC und eigenen Forschungsergebnissen. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Klimafreundliche Bindemittel KW - Betone PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612872 SN - 978-3-9818564-7-7 SP - 22 EP - 29 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61287 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sittner, Jonathan A1 - Hoffmann, T. A1 - Bertmer, M. A1 - Neubert, M. A1 - Schuster, T. A1 - Gluth, Gregor ED - Rogge, Andreas ED - Meng, Birgit T1 - Optimizing calcination methods towards a more sustainable production of calcined clays N2 - Calcined clays are emerging as sustainable alternatives for cement production due to their potential to reduce carbon footprint and energy consumption. This study investigates the calcination of low-grade kaolinitic clays, using rotary kiln and fluidized bed. The calcined clays from the rotary kiln showed enhanced performance in the cement paste. The fluidized bed method demonstrated the potential for significant energy savings, achieving near-complete dehydroxylation with just 30 minutes of calcination. These findings highlight the promise of fluidized bed calcination for efficient clay activation, though further optimization is needed. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Calcination methods KW - Optimizing KW - Blended cement pastes KW - XRD results KW - Thermogravimetric analysis (TGA) PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612891 SN - 978-3-9818564-7-7 SP - 37 EP - 45 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61289 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor ED - Rogge, Andreas ED - Meng, Birgit T1 - Alkalisch aktivierte Bindemittel mit hohem Säurewiderstand für die Kanalsanierung N2 - Die biogene Schwefelsäurekorrosion (BSK) von Betonbauteilen in Abwassersystemen verursacht weltweit hohen Reparaturbedarf. Um zukünftigen Reparaturbedarf zu minimieren, werden für Neubau- und Sanierungsmaßnahmen z. T. Materialien mit besonders hohem Widerstand gegen BSK benötigt. Der vorliegende Beitrag beschreibt Forschungen zu alkalisch aktivierten Bindemitteln, die bei geeigneter Formulierung einen hohen Widerstand gegen BSK bzw. Säureangriff aufweisen. Zusätzlich werden jüngste Fortschritte bei der Bewertung von Methoden zur Prüfung des Widerstands gegen BSK dargestellt. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Säurewiderstand KW - Betonbauteile KW - Abwassersystemen PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613141 SN - 978-3-9818564-7-7 SP - 90 EP - 93 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61314 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nikoonasab, Ali A1 - Müller, Thoralf A1 - Licht, M. A1 - Raupach, M. A1 - Gluth, Gregor ED - Rogge, Andreas ED - Meng, Birgit T1 - Sulfides in the pore solutions of GGBFS-containing concretes - Influence on the corrosion of reinforcing steel N2 - Steel corrosion in sulfide-containing solutions is a challenge in various environments, such as reinforced concrete structures. In concrete, sulfides are introduced by ground granulated blast-furnace slag (GGBFS), used in standard cements and alkali-activated materials (AAMs), affecting steel corrosion. This study examined steel in synthetic GGBFS-containing cement pore solutions using electrochemical techniques. Compared to Portland cement solutions, steel in sulfide-containing solutions exhibits lower open circuit potentials and polarisation resistances. Thus, Portland cement concrete corrosion assessment standards are unsuitable for GGBFScontaining concrete. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Corrosion KW - Reinforcing steel PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612963 SN - 978-3-9818564-7-7 SP - 55 EP - 59 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Law, D. W. A1 - Sturm, Patrick A1 - Gluth, Gregor A1 - Gunasekara, C. A1 - Yamchelou, M. T. ED - Banthia, N. ED - Soleimani-Dashtaki, S. ED - Mindess, S. T1 - Characteristics of high calcium fly ash geopolymer mortar N2 - Portland cement is one of the principal sources of anthropomorphic CO2 emissions. It is estimated that cement production contributes up to 10% of greenhouse gas emissions and annual cement production over 4 billion tons. This has led to the development of a range of alkali activated materials (AAM), the most common precursor materials being class F fly ash and blast furnace slag. At present Class C Fly Ash is not widely utilized as an AAM due to the chemical composition and activation requirements. However, initial research on high Calcium German Class C Fly Ash suggests that the material may have potential for application as an AAM. This paper reports the development of ambient cured alkali activated mortar optimised by varying the alkali modulus and w/b ratio. The evolution of the mechanical and microstructural properties is reported over the initial 28 day period. Compressive strength in excess of 10 MPa at 7 days and 15 MPa at 28 days was achieved at ambient temperature. Similar strengths were observed for both 10% and 15% dosage but as dosage increases the optimal Alkali Modulus reduces. T2 - 77th RILEM Annual Week and the 1st Interdisciplinary Symposium on Smart & Sustainable Infrastructures (ISSSI 2023) CY - Vancouver, BC, Canada DA - 04.09.2023 KW - Alkali-activated materials KW - Brown Coal Fly Ash KW - Lignite Coal PY - 2024 SN - 978-3-031-53388-4 SN - 978-3-031-53389-1 DO - https://doi.org/10.1007/978-3-031-53389-1_8 SN - 2211-0844 SN - 2211-0852 VL - 48 SP - 82 EP - 92 PB - Springer CY - Cham AN - OPUS4-59578 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baer, Wolfram A1 - Holzwarth, Marcel A1 - Mayer, Uwe ED - Vormwald, Michael T1 - Untersuchung des Master Curve-Konzepts für ferritisches Gusseisen mit Kugelgraphit: Versuchswerkstoff und erste Ergebnisse an SE(B)140-Großproben N2 - In einem laufenden Kooperationsprojekt zwischen der BAM Berlin und der MPA Stuttgart wird das probabilistische Master Curve (MC) Konzept nach ASTM E1921 hinsichtlich seiner Übertragbarkeit auf ferritisches Gusseisen mit Kugelgraphit (DCI) untersucht. Zielsetzung ist die Bereitstellung einer Vorgehensweise zur Bestimmung und Bewertung der dynamischen Bruchzähigkeit von DCI im Übergangsbereich. In diesem Beitrag wird der Versuchswerkstoff der Festigkeitsklasse GJS-400 näher vorgestellt. Ferner werden erste Ergebnisse von zwei bruchmechanischen Versuchsserien an SE(B)140-Großproben bei Belastungsraten von ca. 6∙104 MPa√ms-1 bei -40 °C und -60 °C präsentiert. T2 - 56. Tagung des DVM-Arbeitskreises Bruchmechanik und Bauteilsicherheit CY - Kassel, Germany DA - 20.02.2024 KW - Dynamische Beanspruchung KW - Bruchmechanik KW - Master Curve-Konzept KW - Gusseisen mit Kugelgraphit PY - 2024 DO - https://doi.org/10.48447/BR-2024-BB SP - 49 EP - 58 PB - DVM-Verlag CY - Berlin AN - OPUS4-59518 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Holzwarth, Marcel A1 - Baer, Wolfram A1 - Mayer, Uwe A1 - Weihe, Stefan ED - Vormwald, Michael T1 - Untersuchung des Master Curve-Konzepts für ferritisches Gusseisen mit Kugelgraphit: Kritische Belastungsrate und erste Ergebnisse an C(T)-Proben N2 - Im laufenden Verbundprojekt MCGUSS untersuchen dieProjektpartner MPA Stuttgart und BAM Berlin das probabilistische Master Curve (MC) Konzept nach ASTM E1921 hinsichtlich seiner Übertragbarkeit auf ferritisches Gusseisen mit Kugelgraphit (DCI). Ziel des Projektes ist die Entwicklung einer Methode zur Bestimmung und Bewertung der dynamischen Bruchzähigkeit von DCI im Übergangsbereich. In diesem Beitrag werden die Eigenschaften des verwendeten Werkstoffs der Festigkeitsklasse GJS-400 vorgestellt und die sich daraus ergebenden Probenentnahmestellen näher erläutert. Weiterhin werden erste Ergebnisse der C(T)25-Versuchsserien vorgestellt, die bei Belastungsraten von ca. 5∙103 MPa√ms-1, 5∙104 MPa√ms-1 und 5∙105 MPa√ms-1 und einer Temperatur von -40 °C durchgeführt wurden. T2 - 56. Tagung des DVM-Arbeitskreises Bruchmechanik und Bauteilsicherheit CY - Kassel, Germany DA - 20.02.2024 KW - Dynamische Belastung KW - Master Curve KW - Gusseisen KW - C(T)-Proben PY - 2024 SP - 37 EP - 47 PB - DVM Verlag CY - Berlin AN - OPUS4-59519 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Holzwarth, Marcel A1 - Mayer, Uwe A1 - Baer, Wolfram A1 - Weihe, Stefan T1 - Investigation of the Master Curve Concept for Ferritic Ductile Cast Iron N2 - Within fracture mechanics safety assessment for steels in nuclear technology, the probabilistic master curve (MC) concept according to ASTM E1921 is currently used for quasi-static loading conditions as a supplement to the established deterministic ASME reference curve concept. However, for ductile cast iron (DCI), a systematic review of potential modifications to the assumptions and the procedure according to ASTM E1921 and an associated validation are still lacking. For this reason, the application of the fracture mechanics MC concept to ferritic ductile cast iron is being investigated in a joint research project between MPA Stuttgart and BAM Berlin. According to Hojo et al. (2008) the MC concept is already in use for the brittle fracture safety assessment of ferritic forged steel containers, which would suggest an extension to ductile cast iron containers. In compliance with IAEA SSG-26, the safety assessment of DCI containers for transport as well as storage of radioactive materials is based on the fracture mechanics criterion of general exclusion of crack initiation. Within this context, the focus of the current research project is on the further development of brittle fracture safety assessment methods. Therefore, a methodology shall be established to determine and assess dynamic fracture toughness values of DCI in the ductile-to-brittle transition regime, using only a low number of small fracture mechanics test specimens extracted from a component. For the experimental program, a DCI material of grade GJS-400 (GGG-40) has been produced as it is generally used for transport and storage containers for nuclear material. A basic mechanical-technological material characterization consisting of tensile, Charpy, and Pellini tests has been planned and a comprehensive fracture mechanics test program was compiled covering dynamic testing of DC(T)9, C(T)25, C(T)50, SE(B)10, SE(B)25, and SE(B)140 specimens at various loading rates and temperatures. The specimen testing is divided between the project partners based on specimen geometry. MPA Stuttgart has been tasked with the testing of the C(T), DC(T) and Pellini specimens, while BAM Berlin was assigned the SE(B), Charpy and tensile tests. These tests allow for the determination of the loading rate relevant for brittle fracture via C(T)25 specimens and an assessment of size effects by transferring the relevant loading rate to other specimen geometries and sizes. Numerical analyses of different specimen geometries and test setups are planned to investigate the influence of stress triaxiality and loading rate. Furthermore, the time-dependent course of the Weibull stress is assessed via these numerical analyses. Throughout the experimental program, the microstructure-property relationship will also be investigated based on quantitative metallographic and fractographic analyses like scanning electron microscope images and metallographic sections. With the acquired experimental database fundamental assumptions of the MC concept, like the weakest link model and the Weibull distribution, will be assessed for the application to DCI. In the end, the applicability of the MC concept will be evaluated and if necessary, modifications to the MC concept for DCI will be proposed. This paper will present the preliminary results of the GJS400 material characterization and the related selection of test specimen extraction points. First results of the C(T)25 and SE(B)140 specimen testing will also be discussed supported by first metallographic analyses. T2 - SMiRT27 Conference CY - Yokohama, Japan DA - 03.03.2024 KW - Ductile Cast iron KW - Dynamic Fracture Toughness KW - Safety Assessment KW - Master Curve Concept PY - 2024 SP - 1 EP - 10 AN - OPUS4-59302 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gaal, Mate A1 - Wernicke, Pascal A1 - Hufschläger, Daniel T1 - Pulse compression for air-coupled ferroelectret and thermoacoustic transducers N2 - The main advantage of air-coupled ultrasonic testing is the absence of a liquid couplant, which can damage some materials. However, most air-coupled testing scenarios have the challenge of low signals and a signal-to-noise ratio (SNR) several orders of magnitude lower than with couplant-assisted tech-niques. Since this challenge of small SNR also exists in radar technology, the pulse compression used there was adapted and applied to the physical conditions of air-coupled ultrasonic testing. This paper presents ultrasonic transmission measurements on a carbon-fibre-reinforced polymer plate using two experimental setups: 1) a thermoacoustic transmitter and an optical microphone and 2) a pair of ferroe-lectret transducers as transmitter and receiver. Thermoacoustic transmitters convert electrical energy to heat, which causes the air to expand thus producing acoustic waves. The optical microphone is based on a Fabry-Perot interferometer. Ferroelectrets are charged cellular polymers, having piezoelectric proper-ties and excellent acoustic matching to air. Both thermoacoustic transmitters and ferroelectrets are non-linear regarding the relationship between the excited sound pressure and the excitation voltage. Due to these physical boundary conditions, unipolar coding was used to modulate the excitation signals. Vari-ous codes were tested, and parameters of the excitation pulses were varied to find the optimal combina-tion for each experimental setup. The application of pulse compression to the combination of thermo-acoustic transmitter and optical microphone increased the signal-to-noise ratio by up to 16 dB and for the ferroelectret transducers by up to 23 dB. T2 - 30th International Congress on Sound and Vibration CY - Amsterdam, The Netherlands DA - 08.07.2024 KW - Pulse compression KW - Air-coupled ultrasonic transducers KW - Ferroelectret KW - Thermoacoustics PY - 2024 SN - 978-90-90-39058-1 SP - 1 EP - 7 AN - OPUS4-60725 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Reduction of ground-induced building vibrations by kinematic and inertial soil-structure interac-tion and by base isolation N2 - Many buildings on the soil have been measured and the transfer function freefield-to-building is ana-lysed. In general, an amplification at low frequencies, an amplification for the floor resonances, and a reduction for higher frequencies can be observed. Most of the measurement examples show a flexible behaviour along the height of the buildings. The prediction of building vibration consists typically of three steps. At first, the dynamic stiffness of the foundation and secondly the kinematic soil-structure interaction has to be calculated for example by the combined finite-element boundary-element meth-od. The stiffness of the foundation reduces the incoming waves (the kinematic interaction). Finally, the inertial interaction of the building with the foundation soil is calculated by the conventional finite ele-ment method where the dynamic foundation stiffness from the first step is added at the bottom of the building. The building on the compliant soil has a fundamental vertical resonance usually below 10 Hz. A parametrical variation clearly shows the influence of the elasticity of the building on this reso-nance frequency and amplitude. Moreover for column-type office buildings, the low-frequency floor resonances can further reduce this fundamental frequency. A 1-dimensional model has been estab-lished which can well approximate the behaviour of the 3-dimensional building models. It is used to demonstrate the effect of a base isolation with soft elements at the foundation. A rigid building model clearly over-estimates the isolation effect, which is smaller for a model with flexible walls, columns and floors. An even simpler model of an infinitely high building is suggested for the mitigation effect, and the resonance frequency of the rigid building should be replaced by a better performance indica-tor, which is based on the impedance ratio of the isolation and the wall and which can be also ex-pressed as a characteristic frequency. T2 - 30th International Congress on Sound and Vibration CY - Amsterdam, Netherlands DA - 08.07.2024 KW - Building vibrations KW - Base isolation KW - Foundation stiffness KW - Kinematic soil-structure interaction KW - Transfer functions of flexible buildings PY - 2024 SN - 978-90-90-39058-1 SN - 2329-3675 SP - 1 EP - 8 AN - OPUS4-61245 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eberwein, Robert A1 - Hajhariri, Aliasghar A1 - Camplese, Davide A1 - Scarponi, Giordano Emrys A1 - Cozzani, Valerio A1 - Otremba, Frank ED - Di Benedetto, Almerinda T1 - Experimental Research Of A Tank For A Cryogenic Fluid With A Wall Rupture In A Fire Scenario N2 - In the course of decarbonizing the energy industry, cryogenic energy carriers as liquefied hydrogen (LH2) and liquefied natural gas (LNG) are seen as having great potential. In technical applications, the challenge is to keep these energy carriers cold for a long time. This is achieved in the road transport sector and also stationary applications by thermal super insulations (TSI) which based on double-walled tanks with vacuum and multilayer insulation (MLI) in the interspace. This study focuses on the behaviour of widely used combustible MLI in a fire scenario, at vacuum and atmospheric pressure conditions. The former corresponds to the typical design condition and the latter to the condition after an outer hull rapture of a tank. Furthermore, two fire scenarios were taken into account: a standard-oriented approach and a hydrocarbon fire-oriented approach. For the study, a test rig was applied that allows testing of TSI at industrial conditions and subsequent analysis of TSI samples. The test rig allows thermal loading and performance analysis of TSI samples at the same time. Comparing the tests, the samples degraded differently. However, no sudden failure of the entire MLI was observed in any test. These results are relevant for the evaluation of incidents with tanks for the storage of cryogenic fluids and can thus contribute to the improvement of TSI and the development of emergency measures for the protection of persons and infrastructures. T2 - 15th International Symposium on Hazards, Prevention and Mitigation of Industrial Explosions (ISHPMIE) CY - Neapel, Italy DA - 10.06.2024 KW - Liquefied hydrogen KW - Liquefied natural gas KW - Cryogenic storage tank KW - Fire KW - Thermal insulation KW - Multi-Layer Insulation PY - 2024 SP - 707 EP - 717 AN - OPUS4-60460 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo A1 - Davenport, John A1 - Lorek, Andreas A1 - Garland, Stephen A1 - Schwanke, Volker A1 - Wernecke, Roland T1 - Gasfeuchtemessung in der Normung N2 - Schwefelhexafluorid (SF6) ist ein 22.800-mal stärkeres Treibhausgas als CO2, wird aber aufgrund seiner isolierenden Eigenschaften in Mittel- und Hochspannungssystemen wie Schaltanlagen eingesetzt. Voraussetzung für die Durchschlagfestigkeit ist ein geringer Wasserdampfgehalt. Viele aktuelle Feuchtigkeitssensoren zeigen jedoch eine Querempfindlichkeit gegenüber CO2. Diese Richtlinienarbeit zielt darauf ab, den aktuellen Stand der Technik zu erweitern und neue Erkenntnisse zu gewinnen. Abschließend erfolgt eine Erweiterung der Richtlinie zur Gasfeuchte-Messung VDI/VDE 3514. T2 - GMA/ITG – Fachtagung Sensoren und Messsysteme 2024 CY - Nuremberg, Germany DA - 11.06.2024 KW - Gassensorik KW - Industrienormen KW - SF6 PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604597 DO - https://doi.org/10.5162/sensoren2024/P32 SP - 547 EP - 549 PB - GMA/ITG – Fachtagung Sensoren und Messsysteme 2024 CY - Nürnberg AN - OPUS4-60459 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Emmerling, Franziska ED - Rogge, Andreas ED - Meng, Birgit T1 - Exploring new materials for Green Intelligent Building - How can our BAMline help? N2 - In the scope of exploring and characterizing new materials related to Green Intelligent Building (GIB), we will provide an overview of the X-ray spectroscopy and diffraction analytical methods available at the BAMline /1/. and Myspot beamlines. These are two universal beamlines at the Berlin Synchrotron BESSY-II, where BAM has access and supervision role. Overarching electronic and structural properties at different time and length scales, such measurements enable a real-time characterization of materials properties. We will show-case in situ and ex situ deterioration and hydration studies on cement-based constructure materials. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - BAMline KW - Scope of exploring KW - Green intelligent building PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612882 SN - 978-3-9818564-7-7 SP - 30 EP - 36 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61288 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hajhariri, Aliasghar ED - Eberwein, Robert ED - Perrone, Luca pakj ED - Cozzani, Valerio ED - Otremba, Frank ED - Seidlitz, Holger T1 - Study the Impact of Spacer at Thermal Degradation Process of MLI-based Insulation in Fire Condition N2 - To reduce carbon dioxide emissions, energy carries such as hydrogen consider to be a solution. Consumption of hydrogen as a fuel meets several restrictions such as its low volumetric energy density in gas phase. To tackle this problem, storage as well as transportation in liquid phase is recommended. To be able to handle this component in liquid phase, an efficient thermal insulation e.g., MLI insulation is required. Some studies have been revealed vulnerability of this type of insulation against high heat flux, for instance a fire accident. Some investigations have been depicted the importance of consideration of the MLI thermal degradation in terms of its reflective layer. However, limited number of studies have been focused on the thermal degradation of spacer material and its effect on the overall heat flux. In this study, through systematic experimental measurements, the effect of thermal loads on glass fleece, glass paper as well as polyester spacers are investigated. The results are reported in various temperature and heat flux profiles. Interpreting the temperature profiles revealed as the number of spacers in the medium increases, the peak temperature detectable by the temperature sensor on the measurement plate decreases. Moreover, the contribution of each individual spacer in all cases regarding the experimental temperature range is assessed to be around 8%. This value may increase to around 50% for glass paper and polyester spacers, and to around 25% for glass fleece spacers as the number of spacer layers increases up to six layers. To utilize the outcomes of the experiment later and integrate the results into numerical and CFD simulations, a model is proposed for the mentioned experimental temperature range up to 300°C to predict a heat flux attenuation factor. The model proposes a fitting factor that can reproduce the least square fitted line to the experimental data. T2 - 15th International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions Naples (ISHPMIE) CY - Naples, Italy DA - 10.06.2024 KW - Multi-Layer Insulation KW - Cryogenics KW - Liquid Hydrogen KW - Heat Transfer KW - Hydrogen Storage PY - 2024 SP - 744 EP - 755 AN - OPUS4-60461 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eberwein, Robert A1 - Scarponi, Giordano Emrys A1 - Cozzani, Valerio A1 - Otremba, Frank T1 - Lh2 Tanks In Fire Incidents - The Cryogenic High Temperature Thermal Vacuum Chamber Enables In-Depth Insights N2 - Liquefied Hydrogen (LH2) and Liquefied Natural Gas (LNG) establish themselves as important energy carriers in the transport sector. Their storage requires tanks with thermal super-insulations to keep them at cryogenic conditions for a long time. These insulation systems have proven itself in various applications over a long time. However, these insulations are still new in land transportation, where accidents involving collisions, fires, and their combination are to be expected. This study summarizes the results of the ongoing research program in which insulations commonly used in industry were analysed through experimental and numerical studies under fire-like conditions. It was found that there are strong differences among the various insulation systems. Several safety concerns and research gaps exists for layered insulations, which are typically used in land transport. To further analyse these insulation systems, a new test concept called Cryogenic High Temperature Thermal Vacuum Chamber (CHTTVC) was developed and manufactured. This concept enables the testing of large insulation samples under industrial conditions and the consideration of cryogenic conditions relevant for the investigation of various phenomena. The results are important for the evaluation of accident scenarios, the improvement of thermal super-insulations, and the development of emergency measures. T2 - IMECE 2024 CY - Oregon, Portland, USA DA - 17.11.2024 KW - LH2 KW - LNG KW - Fire KW - Insulation KW - Safety PY - 2024 SN - 978-0-7918-8869-8 SP - 1 EP - 7 PB - ASME AN - OPUS4-61751 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Holzwarth, Marcel A1 - Mayer, Uwe A1 - Baer, Wolfram T1 - Investigating the Applicability of the Master Curve Concept for Ductile Cast Iron – Early Results for 2 Different Test Temperatures N2 - Based on the state-of-the-art research and regulations, the application of the fracture mechanics master curve (MC) concept to ferritic ductile cast iron (DCI) is being investigated in a joint research project between MPA Stuttgart and BAM Berlin. This paper outlines the research approach, the planned investigations and first results of the experimental program. T2 - 8th SEDS Workshop: Safety of Extended Dry Storage CY - Garching, Germany DA - 15.05.2024 KW - Dynamic fracture KW - Brittle fracture KW - Ductile cast iron KW - Master Curve PY - 2024 SP - 1 EP - 4 AN - OPUS4-60013 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jaunich, Matthias A1 - Goral, Milan A1 - Sagradov, Ilja A1 - Wolff, Dietmar A1 - Völzke, Holger T1 - Aging investigations of metal seals used in containers for interim storage of spent fuel N2 - For bolted casks for used fuel and high level waste the sealing system has an important impact of ensuring safe enclosure of the inventory The used metal seals show some changes over time which have been addressed for nearly 15 years in running experiments at BAM The observed changes are temperature de pendent and therefore it is expected that test s at higher temperature allow for an acceleration of the effects and ideally the proposal of an ageing model covering the expected time of use . Nevertheless, questions concerning the influence of the experimental approach on the results and effects taking place at the initial days of ageing remain. To address these a new project was launched to give a better understanding of the seal behavior. T2 - PVP2024, Pressure Vessels & Piping Conference CY - Bellevue, WA, USA DA - 29.07.2024 KW - Metal seal KW - Aging KW - Interim storage PY - 2024 SN - 978-0-7918-8851-3 SP - 1 EP - 4 PB - ASME AN - OPUS4-61357 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhadeliya, Ashok A1 - Rehmer, Birgit A1 - Fedelich, Bernard A1 - Jokisch, Torsten A1 - Skrotzki, Birgit A1 - Olbricht, Jürgen T1 - High Temperature Fatigue Crack Growth in Nickel-Based Alloys Refurbished by Additive Manufacturing N2 - Hybrid additive manufacturing plays a crucial role in the restoration of gas turbine blades, where, e.g., the damaged blade tip is reconstructed by the additive manufacturing process on the existing blade made of a parent nickel-based alloy. However, inherent process-related defects in additively manufactured material, along with the interface created between the additively manufactured and the cast base material, impact the fatigue crack growth behavior in bi-material components. This study investigates the fatigue crack growth behavior in bi-material specimens of nickel-based alloys, specifically, additively manufactured STAL15 and cast alloy 247DS. The tests were conducted at 950 °C with stress ratios of 0.1 and −1. Metallographic and fractographic investigations were carried out to understand crack growth mechanisms. The results revealed significant retardation in crack growth at the interface. This study highlights the potential contributions of residual stresses and microstructural differences to the observed crack growth retardation phenomenon, along with the conclusion from an earlier study on the effect of yield strength mismatch on crack growth behavior at a perpendicular interface in bi-material specimens. T2 - Superalloys 2024 Conference CY - Champion, Pennsylvania, USA DA - 08.09.2024 KW - Fatigue crack growth KW - Bi-material structure KW - Additive manufacturing KW - Nickel-based alloys PY - 2024 SN - 978-3-031-63937-1 DO - https://doi.org/10.1007/978-3-031-63937-1_92 SN - 2367-1181 SN - 2367-1696 VL - 15th SP - 994 EP - 1001 PB - Springer CY - Cham AN - OPUS4-60907 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hassenstein, Christian A1 - Hirsch, Philipp Daniel A1 - Wassermann, Jonas A1 - Heckel, Thomas T1 - Automated self-adjustment of array probe with a robotic ultrasonic test system N2 - Ultrasonic testing of objects with complex geometries often requires the use of a robotic arm to position the probe perpendicular to the local surface. Using immersion makes it possible to test these objects with standard ultrasonic linear array probes. Here, the probe positions and orientations provided by the robot are used for merging the locally acquired image data into a 3D-reconstruction. The quality of this reconstruction is highly dependent on the alignment of the position of the physical probe with the position used in the digital model. For common industrial tools, the tool center point (TCP) is usually acquired using geometric features of the tools. However, for ultrasonic arrays in immersion, there is a water standoff between the probe and the test object, therefore the TCP is in free space in front of the array and cannot be acquired with the common method. To overcome this challenge, we propose a method that allows the robotic ultrasonic system to automatically self-adjust the position and orientation of the ultrasonic probe using a test block made of steel with defined geometric features as a target for referencing. For each of the six degrees of freedom, a scan and adjustment routine are established using the data based on the actual ultrasound characteristics of the probe. Given a coarse pre-definition of the tool position and the known target test block, minimal human interaction is required to supervise the adjustment method, leading to higher quality reconstructions than with manual adjustment. T2 - 20th World Conference On Non-Destructive Testing (WCNDT 2024) CY - Incheon, South Korea DA - 27.05.2024 KW - Testing KW - Automation KW - NDT 4.0 KW - Robotics KW - Ultrasonic PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-616387 UR - https://www.ndt.net/search/docs.php3?id=30309 SN - 1435-4934 SP - 1 EP - 9 PB - NDT.net AN - OPUS4-61638 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lecompagnon, Julien A1 - Ricci, M. A1 - Laureti, S. A1 - Ziegler, Mathias ED - Maldague, X. T1 - Practical study on the thermographic detectability of internal defects using temporally structured laser heating N2 - Modern laser systems have proven to be highly versatile heat sources for active thermographic testing. Compared to more traditional light sources, e.g. flash or halogen lamps, their output power can be easily modulated at high rates, allowing a wide variety of complex excitations to be realized. Although their total optical output power can be theoretically scaled to arbitrary values, the maximum output power is practically limited by many factors: the maximum power that the sample under test can absorb without altering the lighted surface itself, the trade-off between irradiance and inspected area, the cost of the laser system, etc. Furthermore, when working with spatial modulator systems, the output power must be limited to avoid damaging such devices. Nevertheless, to guarantee a sufficient amount of heating even for highly thermally conductive materials and/or deeply buried defects, the heating times can be extended, e.g., either by using step heating, long pulse thermography, or by lock-in thermography with a continuously modulated heating. However, for all these approaches, the ranging capabilities of the thermographic defect detection are reduced due to the limited frequency content of the excitation. To tackle this problem, i.e. to increase the excitation energy while preserving its frequency content, new approaches have been developed in the last two decades, among them the use of coded excitations in combination with pulse-compression, and the use of multiple lock-in analysis or a frequency modulated excitation signal. The challenges of such temporally structured heating techniques are manifold, for example, the DC component inherent in optical heating must be taken into account. In general, a wider frequency bandwidth or greater variability of the frequency components also means greater complexity for signal generation and data processing. In this paper, temporally structured excitation schemes with different degrees of complexity are compared on a high-power laser system. T2 - 17th International Conference on Quantitative InfraRed Thermography 2024 CY - Zagreb, Croatia DA - 01.07.2024 KW - Thermography KW - Laser KW - NDT KW - Coded excitation KW - Defect identification PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653790 DO - https://doi.org/10.21611/qirt-2024-077 SN - 2371-4085 SP - 1 EP - 9 PB - QIRT Council AN - OPUS4-65379 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -