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Qualität smarter sichern. Mit einer digitalen Qualitätsinfrastruktur
No full textDie Präsentation fasst die Aktivitäten im Rahmen der Initiative QI-Digital zusammen. Schwerpunkt liegt auf dem digitalen Ökosystem für die Qualitätsinfrastruktur, einer kurzen Vorstellung der beiden Use Cases Additive Fertigung und Wasserstofftankstelle, sowie einem Überblick zu den Begleitaktivitäten
Advanced Materials for the Energy Transition
No full textAdvanced Materials are crucial for the sucess of the energy transition. 10 relevant advanced materials were chosen and their role for relevant technologies was analysed. Challenges regarding their safe and sustainable use are discussed
Metallene Werkstoffe in Geothermieanlagen - nicht nur aus Sicht der Korrosion
No full textUm Konstrukteuren und Nutzern geothermischer Anlagen grundlegende Informationen über die Korrosionsbeständigkeit zur Verfügung zu stellen, wurden verschiedene metallene Werkstoffe, darunter nichtrostende Duplex- und austenitische Stähle sowie eine Nickellegierung, in künstlichen Geothermalwässern, die die Bedingungen an verschiedenen Standorten mit geothermischem Potenzial simulieren, mit Hilfe von elektrochemischen und Langzeittests hinsichtlich ihrer Eignung bewertet.
In hochsalinaren Umgebungen erwies sich Spaltkorrosion als der entscheidende Mechanismus. Die Nickellegierung zeigt eine ausgezeichnete Beständigkeit gegenüber Lochkorrosion. Abgesehen von ihren hohen Kosten eignet sie sich sehr gut für den Bau von Geothermieanlagen mit stark salzhaltigen Fluiden. Rostfreie Stähle und Duplexstähle weisen eine begrenzte Korrosionsbeständigkeit gegen Loch- und Spaltkorrosion auf. Daher sind sie für stark salzhaltige Fluide nicht geeignet. Der Superaustenit zeigt ein temperaturabhängiges Verhalten. In nichtsalinaren Umgebungen könnten niedriglegierte Stähle (neben den höherlegierten Werkstoffen) als Konstruktionsmaterial für Geothermieanlagen eingesetzt werden, sofern eine ausreichende Wandstärke des Materials berücksichtigt wird.
Neben Korrosionsaspekten erwies sich auch die Ausfällung von Fluidbestandteilen als interessantes Thema. Beim Betrieb der Forschungsanlage in Groß Schönebeck wurden Kupfer- und Bleieffekte im Bohrloch festgestellt. Die auftretenden Mechanismen und Maßnahmen zur Verhinderung von Ausfällungen und Abscheidungen wurden ebenso untersucht, wie deren mögliche Einflüsse auf die Korrosionsbeständigkeit metallener Werkstoffe für Anlagenkomponenten.
Der Beitrag beschreibt die Wechselwirkungen zwischen Geothermalwässern und Ausrüstungskomponenten
Translating Flame Retardant Strategies: Analogy from Polyolefins and Bisphenol A polycarbonates to Poly(limonene carbonate)
No full textPoly(limonene carbonate)—PLimC—offers a novel sustainable alternative to traditional polymers, as it is derived from renewable limonene and carbon dioxide as monomers. Proposing PLimC as a future technical polymer for applications in electrical and electronic (E&E) devices, construction, and transportation, PLimC must meet specific fire prevention standards to be deemed suitable. Starting from the chemical structure of PLimC, strategies in analogy to flame retarded bisphenol A polycarbonates (PC), PC blends, and polyolefins (PO) are investigated to identify the most effective route to enhance the flame resistance of PLimC. This study utilized four halogen-free flame-retardant (FR) systems: APP + pentaerythritol (standard intumescent system in PO), a phosphorus flame retardant+PTFE as anti-dripping agent (used in PC blends), metal hydroxide ATH (widely used in PO), and potassium sulfonate salt (specific solution for PC). Applying these FRs at typical PC, PC blends, and PO loadings, we aim to understand their effect on PLimC and evaluated the different flame-retardant routes. Our experimental evaluations focused on the thermal properties, flammability, and fire behavior of each system. ATH emerged as the most effective, reducing the effective heat of combustion from 29.3 MJ kg⁻¹ to 18.6 MJ kg⁻¹ and the total heat evolved from 95 to 55 MJ m⁻². It also resulted in an increase in the limiting oxygen index from 17.1 to 26 vol.-% O2, along with a UL 94 HB40 rating. The intumescent system also exhibited considerable flame retardancy, highlighting the similarity of PLimC’s fire behavior to that of PO rather than P
Links Between Electrode Properties and Cell Performance in Commercial Sodium-Ion Batteries
No full textOur latest results of commercially purchased cylindrical sodium ion battery (SIB) cells will be presented. Two different cell types were dissasembled and thouroughly characterized on electrode as well as on material level.
Both cell types comprise aluminum current collectors for anode and cathode, respectively. Furthermore, geometric electrode parameters, such as electrode size, thickness and loading, will be presented and linked to the electrical data-sheet values. Further in-depth characterization on material level revealed that both cathode active materials are composed of a cobalt free Ni-Mn-Fe-oxide. Interestingly, the cathode particles significantly differ in shape and size between the two cell types. Both anode active materials are graphite-free, and the particle structure points in both cases to a biomass-derived hard carbon material. Based on gas chromatography mesaurements coupled with mass spectrometry (GC-MS), both cell types utilize a mixture of carbonates as electrolyte, however, contain different conductive salts. Moreover, the measured, characteristic electrical features, e.g., capacity, Coulombic efficiency, and initial cycle life, will be discussed. Intriguingly, the cycling stability greatly differs between the cell types. Presumably, this behaviour can be mainly linked to the different morphology of the cathode active material.
Overall, the work can give important insights in the composition and electrical behabiour of currently available SIB-cells
Grundlagen der Korrosion
No full textDer Vortrag behandelt die grundlegenden Reaktionen der Korrosion metallner Werkstoffe und erläutert das Prinzip der Passivität der nichtrostenden Stähle. Zusätzlich enthält der Vortrag beispielhafte Demoexperimente
Korrosionsschutzgerechte Werkstoffauswahl nichtrostender Stähle
No full textDer Vortrag behandelt die systematische Auswahl nichtrostender Stähle unter Berücksichtigung mechanischer, chemischer und wirtschaftlicher Kriterien. Im Mittelpunkt steht das Zusammenspiel von Werkstoff, Medium und Umgebung, das die Korrosionsbeständigkeit als Systemeigenschaft bestimmt. Anhand von Kennzahlen wie Wirksumme, PRE(N) oder MARC wird die legierungsabhängige Beständigkeit gegenüber Loch- und Spaltkorrosion bewertet. Ergänzend werden Einflüsse wie Schwefelgehalt und Zerspanungsgüten auf das Korrosionsverhalten dargestellt. Der Vortrag zeigt praxisorientierte Hilfsmittel zur Werkstoffauswahl – darunter DECHEMA-Werkstofftabellen, ThyssenKrupp-Beständigkeitslisten und normative Vorgaben wie DIN EN 1993-1-4. Zudem werden typische Fehler bei der Werkstoffbestellung und -kennzeichnung erläutert und praxisnahe Empfehlungen gegeben, um korrosionsbedingte Schäden, etwa im Bauwesen oder bei Tunnelinstallationen, zu vermeiden
ChatGPT and epics: LLM enhanced control systems for synchrotron Beamlines
No full textThe presentation describes how large language models (LLMs) such as ChatGPT can be integrated with the EPICS control system to improve the automation and usability of synchrotron beamlines like the BAMline at BESSY II.
It explains how LLMs can interpret natural language instructions, translate them into EPICS commands, and interact with experimental tools to perform complex tasks such as moving motors, running scans, or adjusting beamline components. The system, named P.E.T.E.R. (Performance Enhancing Technology for Experimental Research), supports features like multi-step reasoning, Python scripting, feedback loops, multilingual input, and voice control using OpenAI’s ChatGPT and Whisper
Experimental Study on Thermal Exposure of Pipes to Steady Hydrogen Jet Fire Impingement
No full textJet fires resulting from the accidental release of pressurized hydrogen represent a critical issue, especially due to their potential to trigger a domino effect. The lack of studies on the characterisation of the conditions experienced by, and response of, structures and process equipment directly engulfed in a hydrogen jet fire is of concern to industry. This work presents a characterisation study of a hydrogen jet fire with respect to the conditions experienced by an engulfed object. The total heat flux, along with its radiative component, was measured for hydrogen mass flow rates ranging from 0.05 to 0.2 kg/s. Heat fluxes exceeding 700 kW/m2 were measured at a location that coincided with the point of jet impact. The maximum radiative fraction measured was 20 % at the back of the tube where the specimen could receive radiation from the majority of the flame plume. It is concluded that conditions within hydrogen jet fires are notably more severe than those in hydrocarbon jet fires (for which a heat flux of 350 kW/m2 is considered high). This suggests that PFP systems should not be automatically assumed to provide protection against hydrogen jet fires without further research or actual test evidence of performance
Evaluation and Validation of an Accelerated Weathering Procedure to Characterise the Release of Bisphenol A from Polycarbonate Under Exposure to Simulated Environmental Conditions
No full textBisphenol A (BPA) has been listed as a substance of very high concern (SVHC) due to its endocrine-disrupting properties according to REACH in 2017. European competent authorities have prepared a REACH restriction proposal to reduce BPA levels in the environment. The proposed limit for the concentration of free BPA and other bisphenols in articles is 10 mg kg−1. If exceeded, migration testing can demonstrate that no more than 0.04 mg L−1 is released from the product or material over its lifetime. German authorities are drafting a new restriction proposal after the original was temporarily withdrawn. The residual and migration limits mentioned above were key requirements from the previous restriction proposal. Numerous national and international standards exist for assessing how environmental factors affect the physical and chemical properties of products and materials—such as notch impact strength and tensile strength—but these standards do not cover the release of pollutants. A standardised procedure that covers all aspects of artificial weathering and monitors the subsequent release of pollutants is necessary, especially in the context of the regulation of these substances. An accelerated weathering procedure was established for non-protected samples. This material was not intended for outdoor applications. The testing procedure applied a typical weathering scenario that represents Central European climate conditions. The procedure was validated and applied to samples under distinct quality assurance aspects. Released BPA is quantified via an organic isotope dilution LC-MS/MS method. In parallel, identical samples were weathered outdoors on a weathering rack. Haze and yellowness index are measured to compare outdoor and weathering chamber results