TY - CONF A1 - Duffner, Eric T1 - TFP COD AGE Schallemissionprüfung N2 - Zwischenstand der Ergebnisse der Schallemissionsprüfungen im Rahmen des TFP COD AGE T2 - 5. Projektmeeting COD AGE CY - BAM Berlin, Germany DA - 13.04.2018 KW - Schallemission KW - Composite-Druckspeicher KW - Degradation PY - 2018 AN - OPUS4-44900 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönfelder, Thorsten T1 - Einfluss thermischer Betriebsbelastungen auf die Sicherheit von Typ-III-Druckgasbehältern N2 - Das Einsatzspektrum von den besonders leichten Druckbehältern aus Faserverbund-werkstoffen erweitert sich kontinuierlich. Dies führt dazu, dass mit der erweiterten Verwendung auch die thermisch zulässigen Einsatzgrenzen dieser Behälter ausgeschöpft und sogar teilweise überschritten werden. So können bspw. Atemluftflaschen im Brandeinsatz der Feuerwehr an der Behälteroberfläche derart hohen Umgebungstemperaturen ausgesetzt werden, dass die zulässige Höchsttemperatur von 65 °C deutlich überschritten wird. Durch experimentelle Temperaturversuche an Typ-III-Atemluftflaschen mit einem Innenbehälter aus Aluminium konnte gezeigt werden, dass bei der Brandbekämpfung die untersuchten Atemluftflaschen lokal über das in der Zulassung abgeprüfte Temperaturspektrum erhitzt werden. Der Glasübergangsbereich des Faserverbundwerkstoffs wird partiell um bis zu 95 °C überschritten. Um die reale Sicherheit der Atemluftflasche bewerten zu können, wurde ein analytisches Hybridbehältermodell entwickelt, das die Beanspruchungen mit validierten Materialtemperaturverläufen berechnet. Mit der Einbindung von Schädigungsansätzen konnte ein bisher nicht hinreichend beachtetes thermisches Degradationsverhalten in den Berechnungen berücksichtigt werden. Zudem wurden insgesamt 90 altersbedingt ausgesonderte Feuerwehr-Atemluftflaschen zerstörend geprüft, um nähere Erkenntnisse über den Sicherheitszustand am Ende der Lebenszeit zu erhalten. In diesem Kolloquium werden Forschungsergebnisse vorgestellt, die im Rahmen einer Promotionsarbeit die Auswirkungen dieser erhöhten thermischen Betriebslasten auf eine Typ-III-Atemluftflasche mit einem Innenbehälter aus Aluminium darstellen und bewerten. T2 - BAM-Kolloquium CY - Berlin, Germany DA - 02.05.2018 KW - Druckgasbehälter KW - Thermische Belastungen KW - Degradation KW - Typ-III KW - Faserverbundwerkstoff PY - 2018 AN - OPUS4-44846 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rockenhäuser, Christian T1 - Microstructural investigations of an Al-2618 alloy N2 - Results of Microstructural investigations of an Al-2618 alloy are summrised and discussed. T2 - FVV Arbeitskreissitzung CY - Berlin, Germany DA - 13.05.2015 KW - Aluminium alloy KW - Transmission electron microscopy KW - Microstructure KW - Degradation PY - 2015 AN - OPUS4-42197 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stockmann, Jörg M. T1 - Visualization of low-contrast surface modifications: thin films, printed pattern, laser-induced changes, imperfections, impurities, and degradation N2 - Industrial quality control (QC) nowadays requires the visualization of surface modifications from the macro-scopic to the microscopic or even nanoscopic scale. This is a prerequisite to the evaluation of functionality and reliability, the detection of defects and their separation of artefacts. The diversity of applications ranges from low-E glazings and solar panels, micro- and optoelectronics, micro- and smart devices to sensor-on-chip and lab-on-chip systems [1]. Optical microcopy (light, confocal laser scanning, white light interference) as established QC-tool is operated at normal incidence, i.e. p- and s-polarization are undistinguishable. Either light-intensity in terms of grey scale and colour or intensity-correlated effects of phase shifts are used. In case of ellipsometry, operated at oblique incidence, p- and s-polarization matter, and amplitude ratios and phase shifts upon reflection are measured. Hence, information content must be much higher. The visualization of surface modifications may be very challenging for coating/substrate systems of either al-most identical optical constants, e.g. transparent films on substrates of the same material, or minor film thick-ness, substance quantity and affected area, e.g. ultra-thin or island films. Ellipsometry gives access to the con-trast of intensity (I), amplitude ratio (Ψ), and phase shift (Δ) with nanometer-scaled vertical and micrometer-scaled lateral sensitivity, one is able to identify tiny changes within an unmodified surface. As both mapping ellipsometry (ME) and imaging ellipsometry (IE) are operated in the optical far-field, surface inspection is also possible on the macroscopic scale. Near the Brewster-angle of the bare, undamaged, clean, and fresh substrate, the contrast to add-on and sub-off features is superior. Fig. 1 shows three examples of ellipsometric imaging, i.e. a thin SnO:Ni film on SiO2/Si (Fig. 1a), a dried stain of an anti-body solution on cyclo-olefin-polymer (COP) shown in Fig. 1b, and a polyimide film residue on SiO2/Si (Fig. 1c). For all of these examples, ellipsometry provides much better contrast between substrate and surface modification than optical microscopy, sometimes primarily caused by the oblique incidence (Figs. 1a and 1c), in other cases related to the phase sensitivity of ellipsometry (Fig. 1b). Other examples are laser surface modifications and the corrosion of glass. In these cases, optical microscopy and IE yield to similar results, how-ever only ellipsometry gives access to modelling. Further investigated coating/substrate systems are 100Cr6 steel, native oxide on silicon, borosilicate glass, and the polymer polycarbonate with deposited films of graphene and ta-C:H, printed and dried pattern of liquids such as water, cleaning agents, and dissolved silicone. Besides imaging ellipsometry, referenced spectral ellipsometry (RSE) has been applied, combining the advantages of both optical microscopy (fast measurement) and ellipsometry (high sensitivity to tiny modifications). T2 - International Conference on Spectroscopic Ellipsometry (ICSE-7) CY - Berlin, Germany DA - 06.06.2016 KW - Ellipsometry KW - Thin films KW - Impurities KW - Degradation PY - 2016 AN - OPUS4-37068 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fuchs, S. T1 - Degradation behaviour of polystyrene compounds containing organic disulfides and organic phosphates N2 - A highly efficient flame retardant system containg organic disulfides and phosphorous compounds has been identified and characterised. T2 - PDDG conference CY - Taormina, Italy DA - 04.09.2017 KW - Degradation KW - Polymer KW - Additives PY - 2017 AN - OPUS4-41912 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Richter, Tim A1 - Rhode, Michael T1 - Hydrogen embrittlement and mechanical properties of 9 % Cr P92 steel and P91 weld metal N2 - Martensitic 9 %-Cr steels like P91 and P92 can show an increased susceptibility to delayed hydrogen assisted cracking. The focus of this study was the microstructure and heat treatment effect on the mechanical properties of P92 base material and P91 multi-layer weld metal in both as-welded and post weld heat treated (PWHT) condition. Tensile tests with hydrogen free reference samples and electrochemically hydrogen charged samples were carried out, the mechanical properties were assessed and supported by dedicated fractographic analysis. In addition, hydrogen and microstructure dependent fracture criteria were calculated. All investigated microstructures showed a hydrogen influenced degradation of the mechanical properties compared to the hydrogen free reference samples. In that connection, the as welded martensitic P91 weld metal had the highest degree of degradation in presence of hydrogen. The P91 PWHT weld metal and the P92 base material had comparable properties. From that point of view, a significantly increased risk for hydrogen assisted cold cracking during welding fabrication of P91 weld joints must be considered before any heat treatment is conducted. T2 - IIW Annual Assembly, Meeting of Commission IX-C CY - Tokyo, Japan DA - 21.07.2022 KW - Creep-resistant steel KW - Mechanical properties KW - Hydrogen assisted cracking KW - Weld joint KW - Degradation PY - 2022 AN - OPUS4-55462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Hydrogen embrittlement of steels N2 - Hydrogen assisted cracking of metals is a serious issue in the safety of components, espcially in case of welding. The current presentation gives an overview on specialized testing procedures at Department 9 including the quantitative determination of hydrogen. T2 - HYDROGENIUS BAM Joint Hydrogen Symposium CY - Online meeting DA - 06.07.2021 KW - Hydrogen KW - Embrittlement KW - Degradation KW - Carrier gas hot extraction KW - Welding PY - 2021 AN - OPUS4-53049 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mair, Georg W. A1 - Becker, Ben T1 - Practical applications of CPVs - ESR 11: Accumulation of fibre breaks under time-dependent loads in CFRP materials of composite cylinders N2 - Das Anwendungsspektrum von CPV (composite pressure vessels) ist vielschichtig. Aber auch die Versagensformen und das Spektrum der Messmethoden ist vielfältig. Anhand verschiedener, in der BAM festgestellter Effekte wird gezeigt, warum die micromechnanische Betrachtung des Composties von so großem Interesse für die Vorhersage der Alterung von CPVn ist. N2 - The application range of CPV (composite pressure vessels) is multifaceted. But also the failure forms and the spectrum of measurement methods is manifold. On various, at BAM observed effects, it is shown why the micromechanical analysis of the composites is of such great interest for the prediction of aging effects of CPVs. T2 - Kick-Off Meeting FiBreMoD CY - KU Leuven, Belgium DA - 27.03.2017 KW - Composite KW - Degradation KW - Pressure increase rate KW - Slow burst test PY - 2017 AN - OPUS4-41711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - John, Sebastian A1 - Duffner, Eric T1 - Degradation and damage analysis of composite pressure vessels via experimental modal analysis N2 - For mobile gas storage systems, the application of type IV pressure vessels is state of the art. Type IV tanks consist of an inner polymer liner fully wrapped with fibre-reinforced plastic (FRP). Because of the complex fabric of the FRP as well as a difficulty estimable interaction behaviour between the single components under load, there are still no satisfying non-destructive testing methods to assess the current state of failure nor to estimate the level of degradation accurately and economically. At BAM division 3.5, analysing the ageing process of mobile composite pressure vessels is a major task to ensure safe usage over the whole lifetime. In this context, key aspects of our ongoing research activities are the invention of new test procedures and the development of accurate lifetime prediction models. In order to determine the level of degradation or damage, one meaningful non-destructive approach is to analyse the structural dynamic behaviour via an experimental modal analysis (EMA). Over the last few years, different types and sizes of composite pressure vessels have been tested in several research projects. The presented paper gives an insight into how to extract and interpret modal parameters and how to fit them to the results of residual strength tests. T2 - NOVEM 2023 CY - Auckland, New Zealand DA - 09.01.2023 KW - Pressure vessel KW - Composite KW - Modal analysis KW - Degradation PY - 2023 AN - OPUS4-58063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Thermal desoprtion analysis of hydrogen trapping in micro-alloyed high strength steels N2 - Hydrogen can cause unexpected material failure under consideration of stresses (external/internal) during manufacturing, processing or service of the materials. This failure is mostly based on a certain degradation of the mechanical properties. Thus, the correlation of hydrogen trapping vs. a respective microstructure is necessary for high strength steels. Thus, the scope of this work is the improvement of existing hydrogen trap models by verification of activation energies for hydrogen traps as well as the influence of the determination method. In this scope, the thermal desorption method is appropriate to distinguish between different hydrogen traps. Nevertheless, the specimen temperature has to be accounted very carefully in case of calculating the necessary trap energy. T2 - IIW Intermediate Meeting, Meeting of commission II-A CY - Madrid, Spain DA - 29.02.2016 KW - Thermal desorption analysis (TDA) KW - Hydrogen trapping KW - High strength steels KW - Degradation KW - Heat treatment condition PY - 2016 AN - OPUS4-35544 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -