BAM-Publica - Publikationsserver der Bundesanstalt für Materialforschung und -prüfung
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Unter Druck gesetzt: Die unterschätzte Bedeutung des In-Service-Schweißen an druckführenden, in Betrieb befindlicher H2-Ferngasleitungen
No full textWasserstoff gilt als Energieträger für die Erreichung der Klimaziele und einer nachhaltigen zukünftigen Energieversorgung. Für den notwendigen Transport des Wasserstoffs in großem Maßstab und über weite Entfernungen ist eine zuverlässige Pipeline-Infrastruktur erforderlich. Umfassende weltweite Forschungsprojekte deuten auf die allgemeine Kompatibilität der verwendeten überwiegend ferritischen Stähle für die vorgesehenen Betriebsbedingungen von bis zu 60 °C bei 100 bar Wasserstoff hin. Dies ist jedoch nicht direkt übertragbar auf schweißtechnische Reparatur- und Wartungsarbeiten an im Betrieb befindlichen Pipelines. Ein im Erdgasnetz etabliertes Verfahren stellt das „Hot-Tapping“ dar, bei dem eine unter Druck stehende Pipeline im Betrieb angebohrt wird. Hierfür kommt ein an die Rohrleitung geschweißtes Formstück zum Einsatz, das die Montage der Bohr-/Lochschneidemaschine ermöglicht. In den Richtlinien EIGA 121/14 bzw. AIGA 033/14 wird darauf hingewiesen, dass das Anbohren von Wasserstoffleitungen kein Routineverfahren darstellt: “[…] a hydrogen hot-tap shall not be considered a routine procedure […]“. Dieser Aussage liegt unter anderem zugrunde, dass das Anschweißen des Formstücks an das Rohr und alle zu erwartenden Wärmebehandlungen vor und nach dem Schweißen eine lokale Temperaturerhöhung verursachen. Insbesondere auch an der Rohrinnenfläche, die dem Wasserstoff ausgesetzt ist. Diese erhöhten Temperaturen begünstigen die Absorption und Diffusion von Wasserstoff in das Material. Besonders zu beachten ist außerdem die lokal auftretende kurzzeitige Austenitisierung des Materials, die eine lokal stark erhöhte Wasserstoffkonzentration verursachen kann. Aus den genannten Gründen gibt diese Studie einen kurzen Überblick über die derzeit weltweit verfügbaren Forschungsprojekte zum Schweißen von Wasserstoff-Pipelines im Betrieb. Vorgestellt werden unter anderem erste Ergebnisse des Kooperationsforschungsprojektes H2SuD, das derzeit an der BAM bearbeitet wird
Thermophysically Simulated Weld HAZ and CCT Diagram of High Strength Low Alloy Pipeline Steel
No full textThis study investigates the suitability of low-alloy pipeline steels for hydrogen transportation, focusing on the development of weld microstructures. Previous research has been limited by a deficiency in the understanding of how different microstructural components respond to trapped hydrogen. By developing Continuous Cooling Transformation (CCT) diagrams through dilatometry analysis, this study explores the impact of t8/5-cooling times (the time between 800 °C and 500 °C) on the microstructure and mechanical properties of the HAZ compared to the base material. The findings provide valuable insights into how cooling times influence transformation temperatures and microstructure development, which, in turn, affect hydrogen diffusion and absorption. These findings establish a foundation for future investigations into hydrogen's impact on weld microstructures, including experimental studies, with the aim of optimizing welding practices and enhancing resistance to hydrogen-assisted cracking. Ultimately, this research contributes to improving the safety and reliability of hydrogen transportation systems in commonly used industrial pipeline steels
Digital Twin for Multimodal Synchrotron Experiments
No full textIn this contribution, I present a digital twin-based workflow designed to optimize experimental parameters in X-ray emission spectroscopy (XES), with a focus on reproducibility, data integration, and alignment with FAIR (Findable, Accessible, Interoperable, Reusable) principles in materials science and engineering (MSE). The developed pipeline begins with automated retrieval of crystallographic information from the Materials Project database based on a given sample composition. This structural data is then used to simulate the corresponding XES spectra using FDMNES, allowing for accurate prediction of element-specific emission lines.
The simulated emission lines are fed into an X-ray tracing (XRT) module, which builds a virtual replica of the experimental setup. This digital twin environment enables predictive modeling of spectrometer performance based on geometric configurations. The optimization focuses on two key parameters: the choice of the analyzing crystal and the distance between the sample and crystal (which also defines the crystal–detector distance due to Bragg condition constraints). An active learning algorithm is employed to iteratively adjust these parameters in order to achieve a desired energy-per-pixel (E/pixel) resolution with minimal intensity loss, enabling efficient, data-driven experimental planning.
By integrating data-driven simulations with real-time optimization strategies, this workflow supports efficient experiment planning while minimizing resource consumption and human error. Furthermore, all stages of the process—from data collection and simulation to optimization and visualization—are structured to ensure traceability and interoperability, facilitating future reuse and collaborative research.
I hope this contribution aligns well with the topic “Workflows for FAIR MSE Data” and offers a concrete example of how digital twins can be harnessed to improve the design, execution, and documentation of spectroscopy experiments in the MSE domain
Advancing Industrial Mechanochemistry: Real-Time Insights for Sustainable, Solvent-Free Manufacturing
No full textReactive extrusion has emerged as a continuous approach for conducting mechanochemical reactions on a large scale. However, the use of this method under industrial conditions is hindered by limited understanding. In this study, we unveil the black box of reactive extrusion by employing energy-dispersive X-ray diffraction (EDXRD) to collect time- and spatially resolved in situ data. Our findings demonstrate the EDXRD method’s applicability to a range of chemical transformations and conditions associated with reactive extrusion
Schutzziel-Orientierter Ansatz zum Nachweis der Sicherheit - Handlungsempfehlungen für pränormative Forschung & Handlungsbedarfe für Regulatorik
No full textDer Vortrag beginnt der Erläuterung der zunehmenden Geschwindigkeiten in der eher kontinuierlichen Produktentwicklung rund um Wasserstoff und den unvermeidbar in Stufen arbeitenden Entwicklung von Normen und Vorschriften.
Das führt zu Defiziten in der (sicherheitsorientierten) Verfügbarkeit von Zulassungsgrundlagen. Um das auszugleichen wird vorgeschlagen, auf die Schutzzielfestlegung zu fokussieren, was die genaue Beschreibung des Anwendungsbereiches und evtl. sicherheitstechnischen Hintergrund (Unfälle etc.) mit umfasst. Auf dieser Basis sollten Wirkungsweise entwickelt und diskutiert werden können. Für ein solches System muss es ein klares Rollenverständnis geben.
Als universellsten Ansatz wird die probabilistische Sicherheitsbewertung diskutiert. Dies erfordert klare Vorgaben zu Risikokennzahlen. Als Beispiel werden Wasserstofftransportfahrzeuge mit Größtflaschen über einem Druck-Volumen-Produkt von 1.5 Mio bar Liter vorgestellt.
Um diese Einheiten im Transport zu beherrschen, spielen neue Sicherheitsansätze eine große Rolle. Diese können aber nur dann effizient aufgebaut werden, wenn das einzuhaltende Schutzziel konkret und überprüfbar ist
Reliable physico–chemical characterisation of graphene-related and other 2D materials: present and future
No full textIn the path of commercialisation of graphene-related and other 2D materials the consolidation has begun. In this phase, it is important to build trust between the individual partners in the product value chain. This requires trustworthy statements based on reliable and reproducible material characterisation. The first steps have been taken to measure graphene and other related 2D materials (GR2Ms) under well-defined conditions. Measurands and protocols for key methods were made available for this purpose. But there are still some challenges to overcome such as (i) reference materials, (ii) reference data, (iii) reproducibility throughout the workflow, (iv) credible structure-activity relationships, bringing the standards to (v) the factory floor and to (vi) real-word products. In addition, 2D materials beyond graphene should also be considered exploiting the knowledge gained from the characterisation of GR2M
Fire Test Stand for Thermal Testing of Large Packages for the Transport of Radioactive Materials
No full textPackages for the transport of spent nuclear fuel are designed to withstand severe accidents and must ensure compliance with the IAEA-Regulations prescribing mechanical tests followed by a thermal test. The thermal test involves that a test specimen is exposed to a thermal environment for 30 minutes, simulating the conditions of a hydrocarbon fuel-air fire. The average fire temperature is at least 800°C, and the fire completely engulfs the test specimen. In advance of a regular fire test, BAM performs so-called fire reference tests or calorimeter tests with a fire reference package (FRP) to determine the test conditions for compliance with the IAEA-requirements
Package safety evaluation in a rapidly changing world
No full textThe presentation addressed the evolving challenges and developments in the safety evaluation of transport packages for radioactive materials, especially in light of changing technologies, regulations, and environmental conditions.
A key focus was the current situation in Germany: following the final shutdown of commercial nuclear power plants in 2023, efforts are now concentrated on decommissioning, interim storage in dual-purpose casks (DPCs), and the ongoing site selection process for a repository for high-level waste. The expected duration of interim storage exceeds 100 years, demanding robust and sustainable safety strategies.
One major topic was ageing management, which goes beyond technical measures to ensure transportability over long periods. It also includes preserving knowledge and expertise for future generations. The regulatory framework includes international standards such as IAEA SSR-6 and SSG-26, as well as national guidance like BAM-GGR 023.
It was emphasized the growing role of Artificial Intelligence (AI) in safety evaluations. AI can enhance efficiency through automated document analysis and digital data structuring. However, final safety decisions remain the responsibility of human experts, especially given the complexity of documentation and the shortage of skilled personnel.
The presentation also addressed changing transport technologies, such as the use of electric and hydrogen-powered vehicles. These vehicles behave differently in accidents, particularly in battery fires, which can reach temperatures above 1000 °C and last significantly longer than conventional fires. This raises the need to reassess existing fire test criteria.
Environmental changes were another key point. With global temperatures rising by 0.26 °C per decade, local safety margin evaluations are becoming increasingly important. Existing regulatory assumptions, such as ambient temperatures of 38 °C, may no longer be sufficient.
Finite Element Analysis (FEA) is increasing. AI can support model generation, but there is concern about potential skill fading among engineers. Physical testing, such as BAM’s drop towers (up to 200 tons), remains essential for public package safety acceptance.
Key takeaways from the talk include:
Ageing Management is also about preserving skills and knowledge.
Changing technologies and environmental conditions impact package safety.
AI can improve efficiency but must be used carefully to avoid skill loss.
Physical testing continues to play a vital role in gaining public trust
Low-frequency ultrasound data (pulse-echo technique) of shear horizontal and longitudinal waves acquired on the concrete step specimen “Pk401” with embedded polystyrene foam cuboids
No full textThis dataset includes raw pulse-echo ultrasound measurements of a stepped concrete specimen (ID “Pk401”) from BAM, Berlin. The specimen (2000 × 800 mm) has four thicknesses—573.8, 453.4, 333.1, 210.4 mm—and contains polystyrene cuboids (120 × 120 × 60 mm) centered at depths of 270, 210, 150, and 90 mm. Measurements utilized both shear (M2502) and longitudinal (M2503) probes, combining commercial and in-house BAM equipment
Multivariate evaluation method for the detection of pest infestations on plants via VOC analysis using gas chromatography mass spectrometry
No full textVolatile organic compounds (VOCs) play an important role in the defense against pest infestations on plants. The analysis of these VOCs using gas chromatography mass spectrometry (GC-MS) enables the detection of pests by analyzing the VOC composition (VOC profiles) for specific patterns and markers. The analysis of such complex datasets with high biovariability poses a particular challenge. For this reason, a multivariate evaluation method based on a self-written Python script, using principal component analysis (PCA) and linear discriminant analysis (LDA), was developed and tested for functionality using a dataset, which has been evaluated manually and has identified five specific markers (2,4-dimethyl-1-heptene, 3-carene, alpha-longipinene, cyclosativene, and copaene) for Anoplophora glabripennis (ALB) infestation on Acer trees. The results obtained in the present study did not only match the manually evaluated results, but lead to further insight into the dataset. Another sesquiterpene which is assumed to be alpha-zingiberene was identified as an ALB specific marker in addition to 2,4-dimethyl-1-heptene and 3-carene. Furthermore, the European native beetle species goat moth Cossus cossus (CC) and poplar long-horned beetle Saperda carcharias (SC) were also analyzed for their VOCs to differentiate ALB specific VOC from other pest infestations. This comparison lead to the conclusion that the compounds alpha-longipinene, cyclosativene, and copaene are not specific for ALB but for pest infestation in general. It was possible to identify not only specifically produced VOCs, but also differences in concentrations that arise specifically during ALB infestation. Therefore, the evaluation method for the detection of plant pests presented in this study represents a time-saving alternative to conventional non computing methods, which in addition provides more detailed results