TY - CONF A1 - Hertwig, Andreas T1 - Determining thermal transitions in thin polymer layers by means of spectroscopic ellipsometry N2 - Thin polymer layers have enormous technical significance as polymer coatings on materials are very cost-effective for tailoring properties of surfaces. Apart from technical aspects in their use, thin polymer layers can be used to determine dimensional aspects in properties of material, such as confinement effects. In this work, we investigated several different polymer layer materials and determined their glass transition region by means of temperature-dependent spectroscopic ellipsometry. We have optimised our fitting procedure of the ellipsometric data produced in temperature ramp experiments. By this, we could measure the dependence of Tg on the layer thickness in a wide variety of thickness values, proving the existence of confinement effects in the investigated systems. We compare numerical methods for determining the location of the glass transition and discuss the possibilities of different analysis methods when determining thermal transitions. We also discuss the simultaneous existence of these transitions and annealing effects and the implications on the accuracy of the determined data. T2 - 12th Workshop Ellipsometry 2023 CY - Prague, Czech Republic DA - 18.09.2023 KW - Thin Films KW - Polymers KW - Ellipsometry KW - Themal Transitions PY - 2023 AN - OPUS4-58413 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lengas, Nikolaos A1 - Müller, Karsten A1 - Schlick-Hasper, Eva A1 - Neitsch, Marcel A1 - Johann, Sergej A1 - Zehn, M. W. T1 - FEA of the mechanical response of installed impact target foundations in drop tests of dangerous goods packagings N2 - Packagings for the transport of dangerous goods need to meet special requirements to get an approval. This includes free fall drop testing onto an essentially unyielding surface as a means to assess a package’s resistance to mechanical damage. A main requirement for drop tests is that the impact target’s mass shall be at least 50 times that of the heaviest package to be tested. Nevertheless, many manufacturers do not possess foundation structures with the required mass ratio. Previous evidence highlights that the mass ratio is not a decisive criterion on its own. Parameters such as the impact target foundation’s connection and the impulse experienced by the impacting object are essential as well. However, these factors are not easily verifiable since experimental measurements are not possible at most facilities. The objective of this work is to provide a detailed analysis on the interaction between impact target foundation and subgrade in dynamic impact testing using validated finite-element (FE) models. This research is highly beneficial for industrial application since it allows manufacturers to make informed predictions about the mechanical response of installed impact target foundations. T2 - FEMS EUROMAT 2023 CY - Frankfurt a. M., Germany DA - 03.09.2012 KW - Dangerous goods packagings KW - Drop test KW - Foundation KW - Structural dynamics PY - 2023 AN - OPUS4-58213 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bayerlein, Bernd T1 - PMDco - Platform MaterialDigital Core Ontology N2 - The PMD Core Ontology (PMDco) is a comprehensive set of building blocks produced via consensus building. The ontological building blocks provide a framework representing knowledge about fundamental concepts used in Materials Science and Engineering (MSE) today. The PMDco is a mid-level ontology that establishes connections between narrower MSE application ontologies and domain neutral concepts used in already established broader (top-level) ontologies. The primary goal of the PMDco design is to enable interoperability between various other MSE-related ontologies and other common ontologies. PMDco’s class structure is both comprehensive and extensible, rendering it an efficient tool to structure MSE knowledge. The PMDco serves as a semantic middle-layer unifying common MSE concepts via semantic mapping to other semantic representations using well-known key terms used in the MSE domain. The PMDco enables straight-forward documentation and tracking of science data generation and in consequence enables high-quality FAIR data that allows for precise reproducibility of scientific experiments. The design of PMDco is based on the W3C Provenance Ontology (PROV-O), which provides a standard framework for capturing the production, derivation, and attribution of resources. Via this foundation, the PMDco enables the integration of data from various data origins and the representation of complex workflows. In summary, the PMDco is a valuable advancement for researchers and practitioners in MSE domains. It provides a common MSE vocabulary to represent and share knowledge, allowing for efficient collaboration and promoting interoperability between diverse domains. Its design allows for the systematic integration of data and metadata, enabling seamless tracing of science data. Overall, the PMDco is a crucial step towards a unified and comprehensive understanding of the MSE domain in general. T2 - FEMS EUROMAT 2023 CY - Frankfurt a. M., Germany DA - 03.09.2023 KW - Knowledge Representation KW - Ontology KW - Semantic Interoperability KW - FAIR KW - Automation PY - 2023 AN - OPUS4-58197 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seeber, Henrik T1 - Experimenteller Ansatz zur Untersuchung der primären Explosionswirkung N2 - Explosionsverletzungen gehören zu den häufigsten Verletzungen bei militärischen Einsätzen. Während die Auswirkungen von Splittern, die als sekundäre Explosionsverletzungen eingestuft werden, durch die modernen ballistischen Körperschutzsysteme der Polizei und des Militärs minimiert werden konnten, stellen die Auswirkungen der Stoßwellenausbreitung im Körper als Teil des primären Explosionstraumas nach wie vor eine ernsthafte Bedrohung dar. Zusätzlich zu einzelnen einsatzbedingten Lastfällen liegt ein wissenschaftlicher Fokus auf besonders exponiertem Personal, z.B. aus den Einsatzbereichen „Taktische Zugangstechnik“, „Präzisionsschützenwesen“ oder Steilfeuerwaffen (Mörser). Repetitive mild traumatic brain injury (mTBI) können gesundheitliche Langzeitschädigungen wie und chronic traumatic encephalopathy (CTE) erzeugen. Um einen Beitrag zur Erforschung der primären Explosionswirkungen zu leisten, hat die Bundeswehr in Zusammenarbeit mit dem Bundeswehrkrankenhaus Berlin und der Bundesanstalt für Materialforschung und -prüfung (BAM) ein interdisziplinäres wehrmedizinisches Sonderforschungsvorhaben eingerichtet. Ziel der geplanten Untersuchung ist die Entwicklung einer multidisziplinären Methode zur Analyse des Stoßwellenverhaltens in verschiedenen generischen Gewebesimulanzien, sowie Schutzmaterialien unter möglichst realitätsnahen und reproduzierbaren Bedingungen. Für die Erzeugung reproduzierbarer Stoßwellen wurde ein Autoklav (Druckbehälter) entwickelt, mit dem durch die detonative Umsetzung eines Acetylen-Sauerstoff-Gemisches gut reproduzierbare Druckwellen unter Freifeldbedingungen erzeugt werden können. Vorteile dieser Methode sind unter anderem die kurzen Rüstzeiten zwischen Versuchsdurchgängen, die Minimierung störender Einflüsse im Vergleich zu Stoßwellenrohren und die geringeren Sicherheitsanforderungen im Vergleich zur Anwendung von konventionellen Sprengstoffen. Das generische Torso-Modell besteht in seiner einfachsten Form aus einem mit Druck- und Beschleunigungssensoren instrumentierten Gelatineblock, welcher eine Simulanz für organisches Gewebe darstellt. Zur Untersuchung des Stoßwellenverhaltens wurden verschiedene Medien, wie Hohlkörper, Festkörper und Gewebesimulanzien differenter Dichte in das generische Torso-Modell eingebracht. Einen besonderer Untersuchungsschwerpunkt bildeten die Grenzbereiche zwischen den unterschiedlichen Medien. Des Weiteren wurde analysiert, wie sich verschiedene Schutzmaterialien auf das Stoßwellenverhalten auswirken und mit welchen veränderten Eigenschaften die Stoßwelle anschließend in die Gewebesimulanz einkoppelt. T2 - Angewandte Forschung für Verteidigung und Sicherheit in Deutschland CY - Bonn, Germany DA - 19.03.2024 KW - Primäre Explosionswirkug KW - Blast injury KW - Pressure wave KW - Druckwelle PY - 2024 AN - OPUS4-59474 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cook, Jake Thomas T1 - Assessment of concrete bioreceptivity in algal biofilm green façade systems N2 - Algal biofilm façades are an alternative to traditional green façades which can help to improve biodiversity and air quality within cities. They present a low maintenance approach in which subaerial algae are grown directly on concrete substrates. The intrinsic bioreceptivity of the substrate is a critical factor in successful facade colonisation. Existing research has identified several environmental and material properties which influence concrete bioreceptivity, however a consensus has yet to be made on which properties are most influential and how the interaction between properties may promote algal biofilm growth under specific conditions. T2 - International Conference on Bio-Based Building Materials CY - Vienna, Austria DA - 21.06.2023 KW - Concrete KW - Façade KW - Bio-receptive KW - Extracellular polymeric substances KW - Fractional factorial PY - 2023 UR - https://www.rilem.net/agenda/5th-international-conference-on-bio-based-building-materials-1501 AN - OPUS4-58976 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilling, Markus T1 - PMDco: Achieving High-Quality & Reliable FAIR Data N2 - Knowledge representation in the materials science and engineering (MSE) domain is a vast and multi-faceted challenge: Overlap, ambiguity, and inconsistency in terminology are common. Invariant and variant knowledge are difficult to align cross-domain. Generic top-level semantic terminology often is too abstract, while MSE domain terminology often is too specific. In this presentation, an approach how to maintain a comprehensive and intuitive MSE-centric terminology composing a mid-level ontology–the PMD core ontology (PMDco)–via MSE community-based curation procedures is shown. The PMDco is designed in direct support of the FAIR principles to address immediate needs of the global experts community and their requirements. The illustrated findings show how the PMDco bridges semantic gaps between high-level, MSE-specific, and other science domain semantics, how the PMDco lowers development and integration thresholds, and how to fuel it from real-world data sources ranging from manually conducted experiments and simulations as well as continuously automated industrial applications. T2 - Kupfer-Symposium CY - Jena, Germany DA - 29.11.2023 KW - Ontology KW - Semantic Web Technologies KW - Plattform MaterialDigital KW - PMDco PY - 2023 AN - OPUS4-59031 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Casali, Lucia T1 - Use of the solvent-free mechanochemical method for a sustainable preparation of pharmaceuticals N2 - With the growing interest in environmental issues on the part of governments and institutions, pharmaceutical industries are asked to reduce their environmental footprint. Given the major impact related to the use of solvents, the development of methodologies less solvent demanding is nowadays even more urgent. In light of that, mechanochemistry would be a suitable solvent-free technology since it promotes the activation of the chemical reactions between (generally) solid materials via inputs of mechanical energy. Since such reactions may occur outside the kinetic and thermodynamic rules of conventional solution chemistry, the main limit of mechanochemistry is the poor mechanistic understanding of the solid-state transformations involved, which is still hindering a widespread use of the method, as well a scale-up to the industrial level. However, the development of methods for real-time monitoring of the mechanochemical reactions enables obtaining (in)accessible information on reaction intermediates, new products, or reaction time, thus getting closer to a better understanding of the mechanistic behaviour. With the rules of this chemistry becoming increasingly clear, the new reaction pathways of mechanochemistry wouldn’t represent a limit anymore, but an asset, that may lead to lot of opportunities for the pharmaceutical industry. T2 - Post Doc Day Berlin CY - Berlin, Germany DA - 02.11.2023 KW - Mechanochemistry KW - Sustainability KW - Pharmaceuticals PY - 2023 AN - OPUS4-59010 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Waske, Anja A1 - Fähler, Sebastian T1 - Thermomagnetic generators with magnetocaloric materials for harvesting low grade waste heat N2 - To date, there are very few technologies available for the conversion of low-temperature waste heat into electricity. Thermomagnetic generators are one approach proposed more than a century ago. Such devices are based on a cyclic change of magnetization with temperature. This switches a magnetic flux and, according to Faraday’s law, induces a voltage. Here we give an overview on our research, covering both materials and systems. We demonstrate that guiding the magnetic flux with an appropriate topology of the magnetic circuit improves the performance of thermomagnetic generators by orders of magnitude. Through a combination of experiments and simulations, we show that a pretzel-like topology results in a sign reversal of the magnetic flux. This avoids the drawbacks of previous designs, namely, magnetic stray fields, hysteresis and complex geometries of the thermomagnetic material. Though magnetocaloric materials had been the first choice also for thermomagnetic generators, they require some different properties, which we illustrate with Ashby plots for materials selection. Experimentally we compare La-Fe-Co-Si and Gd plates in the same thermomagnetic generator. Furthermore, we discuss corrosion and deterioration under cyclic use is a severe problem occurring during operation. To amend this, composite plates using polymer as a matrix have been suggested previously. T2 - Dresden Days of Magnetocalorics CY - Dresden, Germany DA - 13.11.2023 KW - Thermomagnetic material KW - Waste heat recovery KW - Generator PY - 2023 AN - OPUS4-58865 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhattacharya, Biswajit A1 - Akhmetova, Irina A1 - Rautenberg, Max A1 - Emmerling, Franziska T1 - Mechanochemical synthesis of phosphonate-based proton conducting metal organic frameworks and hydrogen-bonded metal phosphonates N2 - Proton exchange membrane fuel cells (PEMFCs) are one of the most promising alternative green energy technologies that deliver high energy density without CO2 emissions. The proton conductivity of proton exchange membranes (PEM) contributes to the overall efficiency of a PEMFC. Materials being used as PEMs must exhibit high proton conductivity at the working conditions of the targeted PEMFC. To date, Nafion and Nafion-like polymers with acidic functionality are widely used as membrane materials due to their high proton conductivity in the range of 10-1 to 10-2 Scm-1 at higher relative humidity. However, these materials suffer from high costs, hazardous production process, and poor performance at high temperatures, limiting their versatility. In this context, crystalline porous materials are recognized as promising proton conductors for the proton exchange membrane (PEM) in fuel cell technology, owing to their tunable framework structure. However, it is still challenging bulk synthesis for real-world applications of these materials. Herein, we present mechanochemical gram-scale synthesis of series of mixed ligand metal organic frameworks (MOFs) and metal hydrogen‐bonded organic frameworks (MHOFs) using phenylene diphosphonic acid and 1-hydroxyethylidene-1,1-diphosphonic acid with different bipyridyl type of ligands, respectively. In all cases, the existence of extensive hydrogen bonds with amphiprotic uncoordinated phosphonate hydroxyl and oxygen atoms, the frameworks exhibited high proton conductivity. The study demonstrates the potential of green mechanosynthesis for preparations of framework-based proton conducting materials in bulk scale for green energy generation. T2 - 4th International Conference on Phosphonate Chemistry, Science and Technology, ICOPHOS-4 CY - Crete, Greece DA - 02.10.2023 KW - Proton exchange membrane fuel cells KW - Metal organic frameworks KW - Proton conducting materials PY - 2023 AN - OPUS4-58837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilling, Markus T1 - PMDco - Platform MaterialDigital Core Ontology: Achieving High-Quality & Reliable FAIR Data N2 - Knowledge representation in the materials science and engineering (MSE) domain is a vast and multi-faceted challenge: Overlap, ambiguity, and inconsistency in terminology are common. Invariant and variant knowledge are difficult to align cross-domain. Generic top-level semantic terminology often is too abstract, while MSE domain terminology often is too specific. In this poster presentation, an approach how to maintain a comprehensive and intuitive MSE-centric terminology composing a mid-level ontology–the PMD core ontology (PMDco)–via MSE community-based curation procedures is shown. The PMDco is designed in direct support of the FAIR principles to address immediate needs of the global experts community and their requirements. The illustrated findings show how the PMDco bridges semantic gaps between high-level, MSE-specific, and other science domain semantics, how the PMDco lowers development and integration thresholds, and how to fuel it from real-world data sources ranging from manually conducted experiments and simulations as well as continuously automated industrial applications. T2 - DVM Arbeitskreis Betriebsfestigkeit - Potenziale der Betriebsfestigkeit in Zeiten des technologischen und gesellschaftlichen Wandels CY - Munich, Germany DA - 11.10.2023 KW - Digitalization KW - Semantic Web Technologies KW - FAIR KW - Data Interoperability KW - PMD Core Ontology PY - 2023 AN - OPUS4-58602 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fink, Friedrich T1 - Mechanochemical valorisation of kraft-lignin N2 - As one of nature's largest carbon sources with an annual production of around 20 billion tonnes, lignin is the third most abundant biopolymer on the planet. It becomes available as technical lignin, which is produced as a by-product in the pulp and paper industry and in smaller quantities in second generation biofuel refineries. Current estimates suggest that less than 10% of all technical lignin is reused. The high polydispersity, complex heterogeneous structure and uncertain reactivity are the major limiting factors for further processing. The most common applications for various technical lignins without extensive modifications are for example: Surface active substances, additives in bitumen, cement and animal feed. One way to make lignin usable is to break the structure into oligomer units and thus reduce the polydispersity and average molar mass. In addition, it is advantageous to introduce new functionalities such as hydroxyl or carbonyl groups when splitting the high-molecular-weight (HMW) fractions, or to convert existing functionalities. In this study, a mechanochemical method is presented that can degrade and modify technical kraft lignin by means of sodium percarbonate (SPC). T2 - 10th Intern. Symp. on the Separation and Characterisation of Natural and Synthetic Macromolecules (SCM-10) CY - Amsterdam, Netherlands DA - 01.02.2023 KW - Technical Lignin KW - Mechanochemical oxidation PY - 2023 AN - OPUS4-57001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, M. A1 - Schlingmann, T. A1 - Schmidt, J. A1 - Bettge, Dirk A1 - Hilgenberg, Kai A1 - Binder, M. A1 - Klöden, B. T1 - A Round Robin Test To Investigate The Printing Quality Of PBF LB/M Processed AlSi10Mg N2 - When it comes to higher accuracies, new technologies and real applications in additive manufacturing, there is one topic which cannot be avoided: The material response on the chosen processing parameters and its agreement and correspondence with literature data of the wrought material grade counterpart. In industrial Additive Manufacturing (AM) standards in terms of printing parameters, protection gas atmospheres or powder handling instructions are not obligatory. Therefore, the question must be answered whether the AM process is reproducible and reliable over different printing companies. This was the motivation to realize a round robin test between 8 European printing companies and academic partners. The consortium had printed and tested fatigue and tensile testing bars under plant-specific conditions. A commonly used cast aluminum alloy, AlSi10Mg, was chosen as test material for the PBF-LB/M process. Differences of the results between the partners and the scatter itself were discussed in detail. T2 - World PM2022 CY - Lyon, France DA - 09.10.2022 KW - Additive manufacturing KW - AlSi10Mg KW - Laser powder bed fusion KW - Round robin KW - Reproducibility PY - 2022 AN - OPUS4-56303 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Linberg, Kevin T1 - Polymorphism in molecular cocrystals controlled by variable temperature ball milling N2 - Mechanochemistry offers a unique opportunity to modify or synthesize new crystal forms. Although the method is very promising, little is known about the mechanochemical means to control the synthesis of a solid form. Using an polymorphic organic cocrystal system, we show here that mechanochemistry can be used to obtain a polymorph transformation under the apparently conventional (thermal) transition point. T2 - Bessy User Meeting 2022 CY - Online meeting DA - 08.12.2022 KW - Mechanochemistry KW - Polymorphism KW - TRIS PY - 2022 AN - OPUS4-56473 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Karafiludis, Stephanos T1 - How do transition metal phosphates crystallise? N2 - Industrial and agricultural waste streams (waste waters, sludges, tailings etc.), which contain high concentrations of NH4+, PO43- and transition metals, are environmentally harmful due to their toxic pollutants. At the same time, phosphorus and selective transition metals such as Cobalt could be potentially depleted as a critical raw material due to the high demand and rapidly declining natural ore deposits. Therefore, due to simultaneous scarcity and abundance, the phosphorus and 3d metal recovery from agricultural, industrial, mining, or urban wastewaters have been an important factor in sustaining our global consumption and preservation of the natural environment. Typically, separate pathways have been considered to extract hazardous substances such as transition metals or phosphate, independently from each other. Here, we investigate the crystallization of transition metal phosphate (TMP) compounds (NH4MPO4∙6H2O, M3(PO4)2∙8H2O with M = Ni2+, Co2+, NixCo1-x2+ M-struvite and M-phosphate octahydrate) out of aqueous solutions, which allow for P, ammonia and metal co-precipitation. The precipitation of these compounds from industrial and agricultural waste waters has high potential as a P- and 3d metal recovery route. For this purpose, a detailed understanding of the crystallization process beginning from combination of solved ions and ending in a final crystalline product is required. Through adjusting the reaction conditions, the stability, crystallite size and morphology of the as-obtained TMPs could be controlled. Detailed investigations of the precipitation process in time using ex- and in-situ techniques provided new insights into their non-classical crystallization mechanism/crystal engineering of these materials. These TMPs involve transitional colloidal nanophases during the crystallization process. Over time, their complex amorphous framework changes significantly resulting simultaneously in an agglomeration and densification of the compound. After extended reaction times these colloidal nanophases condensed to a final crystal. However, the reaction kinetics of the formation of a final crystalline product and the lifetime of these intermediate phases vary significantly depending on the metal cation involved in the precipitation process. Ni-struvite is stable in a wide reactant concentration range and at different metal/phosphorus (M/P)-ratios, whereas Co tends to form Co-struvite and/or Co-phosphate octahydrate depending on the (M/P)-ratio. The mixed NixCo1-x system shows a significantly different crystallization behavior and reaction kinetics of the precipitation compared to the pure endmembers. The observed various degree of stability could be linked to the octahedral metal coordination environment in these compounds. The achieved level of control over the precipitates, is highly desirable for 3d- and P-recovery methods. Under this paradigm, the crystals can be potentially upcycled as precursor materials for (electro)catalytical applications. T2 - Granada Münster Discussion Meeting (GMDM) CY - Granada, Spain DA - 30.11.2022 KW - Struvite KW - Transition metal KW - Phosphates KW - Amorphous phases KW - Non-classical crystallization PY - 2022 AN - OPUS4-56478 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Karafiludis, Stephanos T1 - Crystallization study of transition metal phosphates: a new example for non-classical crystallization theory N2 - Industrial and agricultural waste streams (waste waters, sludges, tailings etc.), which contain high concentrations of NH4+, PO43- and transition metals, are environmentally harmful due to their toxic pollutants. At the same time, phosphorus and selective transition metals such as Cobalt could be potentially depleted as a critical raw material due to the high demand and rapidly declining natural ore deposits. Therefore, due to simultaneous scarcity and abundance, the phosphorus and 3d metal recovery from agricultural, industrial, mining, or urban wastewaters have been an important factor in sustaining our global consumption and preservation of the natural environment. Typically, separate pathways have been considered to extract hazardous substances such as transition metals or phosphate, independently from each other. Here, we report the synthesis routes for transition metal phosphate (TMP) compounds (M3(PO4)2∙8H2O, NH4MPO4∙6H2O, M = Ni2+, Co2+, NixCo1-x2+ M-struvite and M-phosphate octahydrate), which allow for P, ammonia and metal co-precipitation. The precipitation of these compounds from industrial and agricultural waste waters could be a promising P-recovery route. Through adjusting the reaction conditions, the stability, crystallite size and morphology of the as-obtained TMP could be controlled. Detailed investigations of the precipitation process using ex- and in-situ techniques provided new insights into their non-classical crystallization mechanism/crystal engineering of these materials. These TMPs involve transitional colloidal nanophases which subsequently aggregate and condense to final crystals after extended reaction times. However, the reaction kinetics of the formation of a final crystalline product vary significantly depending on the metal cation involved in the precipitation process. Ni-struvite is stable in a wide reactant concentration range and at different metal/phosphorus (M/P)-ratios, whereas Co tends to form Co-struvite and/or Co-phosphate octahydrate depending on the (M/P)-ratio. The mixed NixCo1-x system shows a significantly different crystallization behavior and reaction kinetics of the precipitation compared to the pure endmembers. The observed various degree of stability could be linked to the octahedral metal coordination environment in these compounds. The achieved level of control over the precipitates, is highly desirable for 3d- and P-recovery methods. Under this paradigm, the crystals can be potentially upcycled as precursor materials for (electro)catalytical applications. T2 - Adlershofer Forschungsforum 2022 CY - Berlin, Gemany DA - 11.11.2022 KW - Transition metal KW - Phosphates KW - Non-classical crystallization KW - In-situ SAXS/WAXS KW - Cryo-TEM PY - 2022 AN - OPUS4-56479 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Epperlein, Martin T1 - QI-Digital - Qualitätssicherung für die Additive Fertigung N2 - Für die konventionelle Fertigung hat sich das bestehende System der Qualitätsinfrastruktur (QI) bewährt. Die additive Fertigung vergrößert den gestalterischen Spielraum von möglichen Bauteilgeometrien und Prozessfehlern jedoch erheblich. Hier gerät die QI an ihre Grenzen, sodass die Fertigung und Zulassung sicherheits-relevanter Bauteile sehr zeit- und kostenintensive Versuche erfordern. Eine moderne digitale QI erlaubt eine effizientere Qualitätssicherung für additiv gefertigte Bauteile. Dies erfordert eine durchgängig digitale Abbildung des physischen Materialflusses. T2 - QI-Forum CY - Berlin, Germany DA - 11.10.2022 KW - Additive Fertigung KW - Qualitätssicherung KW - Digitalisierung PY - 2022 AN - OPUS4-56382 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strauß, Lea T1 - Empirical Model for Fatigue Life Prediction N2 - Laser-based powder bed fusion (PBF-LB) is an advanced additive manufacturing technique renowned for its precision and capability to fabricate complex metal components. However, the high thermal gradients and rapid cooling rates intrinsic to this process introduce significant process-induced effects, such as inhomogeneities, surface roughness, anisotropy, and residual stress, all of which critically influence the fatigue behavior of the produced parts. This study investigates the fatigue performance of AlSi10Mg samples produced by PBF-LB, examining the impact of varying surface conditions, geometries, and residual stress levels. Fatigue life prediction models are formulated based on nominal stress amplitude, residual stress, notch factor, crackinitiating inhomogeneity, and surface roughness, with smooth samples serving as a baseline reference. The study presents two empirical models for predicting fatigue life and fatigue strength using S-N curves and the Kitagawa-Takahashi diagram with the El Haddad approach, derived from comprehensive experimental data, including finite element modelling, fatigue life measurements, surface roughness evaluations, and residual stress analysis. T2 - ICAM2024 CY - Atlanta, GA, USA DA - 28.10.2024 KW - AlSi10Mg KW - Kitagawa-Takahashi diagram KW - Equivalent stress KW - Fatigue life prediction KW - PBF-LB/M PY - 2024 AN - OPUS4-61538 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina T1 - Supramolecular Polymerization Induced by Confined Structural Water in Small Crown Macrocycle N2 - Structural water, integral to biological systems, i.e., for protein stability and function, has rarely been explored in materials science. Supramolecular polymers, which assemble through non-covalent interactions, offer functionalities such as responsiveness and self-healing. Traditionally, in such systems water is considered as a solvent. Herein, a novel water-induced supramolecular polymer hydrogel is reported, formed by a single crown ether macrocycle with a selenoxide hydrogen bonding receptor and a hydrophobic selenium-substituted core. Structural water was confined in a nanosegregated three-dimensional architecture, maintaining water in a liquid-like state down to -80 °C. Unlike previous studies requiring multiple crown ether units for structural water formation, this single unit system effectively controls structural water and supramolecular polymerization. The presence of confined water was revealed through dielectric and Flash DSC experiments. The resulting hydrogel exhibits exceptional adhesion to hydrophilic surfaces, retaining strength at low temperatures. These findings demonstrate the significant role of a single macrocycle in governing water structure and functionality in supramolecular systems. An expansion of the understanding of water's role beyond a solvent has been achieved, showcasing its potential as a comonomer in material science, particularly in the development of responsive, adhesive supramolecular polymers and hydrogels. T2 - Polydays 2024 CY - Berlin, Germany DA - 30.09.2024 KW - Hydrogels KW - Structural water PY - 2024 AN - OPUS4-61658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Melzer, Michael T1 - The temperature DCC exposed N2 - The DAkkS-accredited calibration laboratory of the German Federal Institute for Materials Research and Testing (BAM) has established valid XML digital calibration certificates (DCCs) for calibrations of resistance thermometers within the scope of its accreditation. Hence, all necessary information according to ISO/IEC 17025 and the DKD-R 5-1 calibration rule is provided in a machine-readable and machine-interpretable form. Furthermore, we actively participate in the definition of general and community-specific good practice requirements for the DCC of temperature quantities as technical specifications, hosted by the German Calibration Service (DKD). In this contribution the entire XML source code of a DCC from a Pt 100 thermometer calibration will be exposed and discussed. The DCC was automatically generated using a self-implemented middleware that is compiling the metadata (i.e. customer-, order-, item- and method data) and combines it with the measured calibration data and influence conditions into a process- and lab-specific DCC template. Since it was issued as an accredited calibration certificate, the validated and authorized DCC is also equipped with the novel digital accreditation symbol to form an `eAttestation´. This advanced electronic seal with a qualified certificate was recently piloted with the German national accreditation body (DAkkS), and, after successful validation by the receiver, verifies the active accreditation status of the issuing body at the time of sealing (authorization). As it also provides all other functionalities of an electronic seal, (i.e. data integrity and authenticity), it can fully replace a digital signature on accredited DCCs. The presented temperature DCC architecture fully complies to the latest good practice definitions of the DKD and thus represents a level 4 DCC according to the utility model for machine interpretability of DCCs. This also includes basic and quantity-specific refType definitions that are linked to an online refType repository to harmonize these key semantic providing elements across other DCC-issuing laboratories. The paper and also its conference poster will not represent a general introduction and motivation for the DCC itself. It rather addresses more detailed aspects of good practice, especially for DCCs from temperature quantity calibrations and may stimulate in-depth discussions between DCC experts from the providing, utilizing and accrediting points of view. The work was performed within the national QI-Digital initiative of the German Federal Ministry for Economic Affairs and Climate Action. T2 - IMEKO 2024 XXIV World Congress CY - Hamburg, Germany DA - 26.08.2024 KW - Digital Calibration Certificate KW - E-Attestation KW - QI-Digital KW - Digital Metrology KW - Calibration PY - 2024 UR - https://www.imeko2024.org/home AN - OPUS4-61872 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schob, Daniela T1 - Comparative Analysis FFF vs. cold rolled 316L Samples N2 - This study provides insights into the properties of 316L stainless steel produced by additive manufacturing using fused filament fabrication (FFF). One key finding is particularly noteworthy: in significant contrast to cold-rolled 316L, FFF316L develops a pronounced martensite phase after fabrication. The comprehensive comparative analysis shows that FFF316L not only retains the ferrite volume content, but that this is also significantly influenced by the build-up direction. Despite the sintering process, which typically involves densification of the material, a pore volume fraction of 8.45 % remains, which influences the mechanical properties. Although FFF316L has lower elastic modulus and tensile strength values compared to cold-rolled 316L, its ductility is still competitive. The study further reveals that deformation-induced martensite forms at the intersections of the deformation twins and ferrite islands form at the grain boundaries during the compression and sintering phases. These findings highlight the challenges associated with FFF316L in specific application fields and signal the need to continue to carefully evaluate and improve the development of manufacturing technologies. T2 - 4th Symposium on Materials and Additive Manufacturing - Additive 2024 CY - Berlin, Germany DA - 12.06.2024 KW - Additive manufacturing KW - Fused Filament Fabrication KW - Computed Tomography KW - 316L Stainless Steel KW - Deformation-Induced Martensite PY - 2024 AN - OPUS4-60302 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -