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9. Nachtrag zum Zulassungsschein 08/BAM IV.3/12/10 für Bewehrungsgitter aus Kunststoff für Deponieoberflächenabdichtungen
No full text9. Nachtrag zum Zulassungsschein 08/BAM IV.3/12/10 für Bewehrungsgitter aus Kunststoff für Deponieoberflächenabdichtungen der Firma HUESKER Synthetic GmbH, Gescher
Fire Retardancy Featuring Sustainability: Food for Thought between Fake Fiction and Future
No full textSustainability, or in other words, exploiting resources under the terms of environmental conservation for the economic welfare and prosperity continuously over time, would revolutionise the plastics industry were it to become predominant practice as a linear, fossil-fuel–based economy is switched to a carbon circular economy. Food for though is given by dint of a critical overview of the current trends and mainly by sketching our own key projects performed in the field of sustainable flame-retardant polymeric materials in the recent years
Knowledge Infrastructure supporting image-based characterisation of 2D graphene materials
No full textTo better understand the relationship between image features and biological effects such as toxicity,we have developed a method combining image thresholding and pixel-wise segmentation to create annotated datasets. These datasets are used to train machine learning models and establish human–AI learning loops for material classification and structure detection. We employ deep learning architectures such as ResNet, EfficientNet, and U-Net to automate the classification and segmentation of SEM/TEM images of 2D nanomaterials, with targeted manual annotation focusing on key structures (graphene flakes, agglomerates, contaminants, etc.). This approach ensures reproducible, large-scale analysis, which is essential for studying the links between structure and biological response. Finally, our methodology aligns with OECD requirements and contributes to the Safe and Sustainable by Design (SSbD) framework, aiming to enhance product reliability and sustainability
Searching for the first sign - crack initiation under fatigue loading in seawater-corroded structural S355 steel
No full textCorrosion caused by direct contact with seawater is the most important problem for technical systems and components made of steel in the maritime sector (quote). The loss of material associated with general corrosion leads to a weakening due to the associated reduction in cross-section. Besides, stress concentrations will occur at localized areas of corrosion called corrosion pits. With repeated loading, such pit may act as a nucleation site for fatigue cracks, which ultimately lead to the degradation of the fatigue strength of the material (quote). Due to the random nature of the spatial occurrence of such localized corrosion, the prediction of service life under fatigue loading is made even more difficult. Research shows that a significant portion of fatigue life is spent in the transition of a corrosion pit to a short fatigue crack and in the growth of such short cracks [1]. As a part of the MAXWind project, numerical models are developed that incorporate the evolution of pit morphology due to corrosion [2], associated geometric stress concentration [3], and pit to crack transition [4]. Experiments that represent actual corrosion pits are thus required to verify and validate such models and to determine the model parameters.
As part of the project, structural steel coupons (used for manufacturing wind turbine monopile structures) were directly exposed to seawater in an offshore facility for 22 months. Subsequently, dog-bone shaped specimens were extracted from coupons from different corroded contact areas (underwater, water level, splash zone) for fatigue strength evaluation. This article describes selected results of fatigue tests (purely tensile at different load levels. The sample surfaces were monitored with an IR camera during the entire fatigue test. The aim of this observation was to record the spatial temperature distribution which can be correlated to the stress distribution on the sample surface. The occurrence of cracks is characterized by the appearance of closely neighboring regions with reduced (at the crack flanks) and increased (at the crack tip) internal stress [5]. The resulting temperature differences are very small but can be quantified using the lock-in technique (i.e. TSA - thermal stress analysis). In this study, different thermal signatures are considered, which can be used as an indicator for the first occurrence of macroscopic cracks
NICOLHy - 3rd Stakeholder Advisory Board meeting
No full textThe NICOLHy project aims to develop a novel insulation concept based on Vacuum Insulation Panels (VIP) that enables the safe, cost- and energy efficient storage of large quantities of LH2. Such large scale LH2 storage technology is necessary for establishing a hydrogen economy with dimensions between 40.000 m³ and more than 200.000 m³ of LH2. However, new design concepts are needed because the currently available technologies used in small and medium storages today are not suitable for up-scaling. The main problems prohibiting the up-scaling are the long production time due to the process chain, the low failure tolerance and the spherical shape, which reduces the payload in technical applications by up to 50% compared to other shapes. The novel concept will change these conditions by a system which is modular, open-form, time-and cost efficient while production, operation and service, multi-failure tolerant and applicable for onshore and offshore applications. The presentations shows details to the concept and presents several safety concerns the project has to deal with
The next steps in the standardisation of graphene-related and other 2D materials (GR2M)
No full textThe first products with graphene-related 2D material (GR2M) are on the market. In this phase trust is essential for the commercial success of these products, between the individual partners of the product value chain, and between the manufacturer and the consumer. Standards are an important tool for building this trust. The first steps have been taken in standardisation, e.g. in terminology and the characterization of raw materials. But there are still some challenges to overcome such as bringing the standards to the factory floor and real-world products. For the validation of new protocols and methods there is a need of reference data and materials. But not only the measurement should be reproducible, the whole analytical workflow from sample storage and preparation to data analysis should be reproducible. Another important issue is the establishment of credible structure-activity relationships which allows the prediction of the properties of the GR2M, but also of the biological activity including the safety for the human health and the environment. Such relationships can be used for read-across and grouping and can facilitate the regulation of the advanced materials.
In addition, 2D materials beyond graphene should also be considered and can benefit from the experience from the standardisation of graphene and graphene oxide
Ermittlung wasserstoffabhängiger, mechanischer Eigenschaften der Schweißnahtgefüge niedriglegierter Stähle für Ferngasleitungen
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
Wire-Print as a Sample Preparation Procedure Suitable for Accurate Morphological Characterization of Constituent Particles for Graphene-Related 2D-Materials
No full textIn this study we have systematically tested the efficacy of a new deposition procedure for graphene-related 2D materials (GR2M’s) from liquid suspension onto a substrate for quantitative analysis of their size and shape distribution with electron microscopy.
The technique is an extension of the conventional drop-casting method, and we have designated it “wire-print” deposition. It consists of two steps, first one being usual drop-casting on a copper substrate and second one involving a thin copper wire with a sub-mm diameter being dipped into the deposited droplet and retracted with a corresponding half-spherical droplet attached on its tip and final deposition of this entire nL-amount of suspension onto e.g. a silicon wafer for microscopical, detailed analysis. 11 series of such a wire-print deposition for a graphene-based ink have been considered, whereby various conditions (treatment of the starting suspension) have been experimented with a repetition of up to 10 times per condition, all together 86 spots on a silicon wafer of 10 mm x 10 mm. The evaluation of one series of 8 repeated wire-print depositions reveal that the deposited spots are visualized with SEM. The weak presence of coffee-rings, irregular spot shape, and presence of agglomerates should be noticed. Both the mean value of the 8 ECD distributions and the total number of flakes deposited in each spot show a variance in the range of 17% and 22%, respectively. In the context of accurate analysis of such challenging complex materials these numbers can be considered as excellent and demonstrate the high benefit of the wire-print deposition for accurate morphological measurements on GR2M’s
AI-Based Documentation Analysis for Safety Assessment of Packages for Radioactive Material
No full textThe transportation of radioactive material requires, dependent on type and quantity of the radioactive material, a regulatory approval based on the package type. Safety assessments shall be conducted in compliance with the International Atomic Energy Agency (IAEA) regulations and documented in a comprehensive package design safety report to obtain approval from authority. This comprehensive safety report evaluates a broad range of requirements from the regulations, including mechanical, thermal, shielding, criticality and transport requirements and controls, and testing assessments. Additionally, it encompasses supporting documents such as specifications, inspections, certifications, drawings, and guidelines in a variety of complex documents.
Safety and manufacturing reports contain multiple interconnected sub-reports covering various topics. Changes, such as component modifications, material property updates, or regulatory revisions, often impact multiple sections of the safety analysis reports, making even minor adjustments complex and time-consuming. Each transport package has unique requirements to be fulfilled, making every safety report distinct, despite following the same regulatory framework.
Most documentation exists in standard digital formats but is often not machine interpretable, preventing automated analysis of the critical dependencies between them. This paper argues that moving beyond simple digitization towards structured knowledge representation is essential for addressing these challenges. We propose a multi-stage approach, beginning with foundational AI technologies such as Large Language Models (LLMs) and Retrieval-Augmented Generation (RAG), and progressing toward the construction of Knowledge Graphs (KGs). KGs convert unstructured and semi-structured information into a connected, queryable network, enabling precise tracing and visualization of complex interdependencies within the documentation landscape.
By linking interpretable content directly to datasheets, tables, simulations, experimental results, standards, and regulations, such a system would automatically identify changes and interdependencies. Related conditions could be validated using AI-based tools, reducing the need for manual intervention, improving both efficiency and safety.
Human error plays a significant role in drafting, reviewing, and revising safety reports, often requiring iterative review cycles and multiple reviewers before approval. A digital quality infrastructure could reduce iterations and further improve efficiency. Integrating AI into this process could optimize safety assessments and enhance their robustness by leveraging interpretability to enhance safety.
This preliminary study explores the readiness and requirements for using intelligent documentation analysis system in the context of regulatory compliance for package safety for the transport of radioactive material. By analysing current documentation workflows, we identify how LLM-based tools can interpret complex safety reports and highlight critical interdependencies and then demonstrate why a KG-based architecture is necessary to robustly manage and query critical interdependencies. This lays the groundwork for future agentic AI systems capable of proactively supporting the safety assessment lifecycle, while stressing the importance of robust data governance and AI reliability in this highly regulated context
Towards a simplifiedmodel of the delayed impact: numerical and experimental outlook
No full textThe IAEA Regulations for the Safe Transport of Radioactive Material No. SSR-6 require drop tests for demonstrating the ability of a package to withstand accident conditions of transport. In case a gap exists between the contents and the lid, it can result in a delayed impact of the content onto the lid system during a vertical drop test. The kinematic energy transmitted to the lid in such cases can be significant due to the stiffness of the impact, leading to high stresses in the bolts compared to a configuration without a gap.
In the past, IRSN and BAM have individually investigated the modelling of the delayed impact phenomenon. BAM has examined the effects of the delayed impact phenomenon for spent fuel packages in a comparative analysis between experiments and simulations, which was presented at SMIRT 2013. Meanwhile, IRSN’s has developed a simple numerical tool that can quickly evaluate the influence of various parameters before considering a more complex finite element numerical calculation. This tool was presented at PATRAM 2022.
In 2023, BAM and IRSN (now ASNR – French nuclear safety and radiation protection authority) decided to jointly pursue their study on the delayed impact phenomenon, incorporating damping effects, by developing new insights and techniques. To this end, a controlled and simplified set of experiments needs to be developed to calibrate and validate the simplified model. These experiments will record velocity, position of parts, strain and accelerations. The parameters and configurations necessary for the development of the mock-up, as well as the placement and quantity of sensors, are determined through extensive pre-calculations using both complex finite element models and the simplified approach. A key challenge involves precisely controlling the drop of the mock-up to accurately replicate the theoretical contact and damping conditions. Advanced sensor technologies will be employed to acquire reliable and sufficient data. The tests are designed and conducted at BAM's TTS drop test facility in collaboration with ASNR