TY - CONF A1 - Schmidt, Anita T1 - Eine sichere Zukunft für Lithium-Ionen Batterien N2 - Eine sichere Zukunft hat eine Technologie dann, wenn sie die Gesellschaft auch von ihrer Sicherheit überzeugen kann. Dies ist insbesondere für Lithiumbatterien von hoher Bedeutung. Die BAM trägt auf den verschiedene Ebenen auf vielfältige Art und Weise dazu bei, diese Sicherheit zu untersuchen und zu verbessern. T2 - 4. Batterieforum Berlin Brandenburg CY - Potsdam, Germany DA - 22.11.2024 KW - LIthiumbatterien KW - Sicherheit PY - 2024 AN - OPUS4-62328 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Widjaja, Martinus Putra T1 - Accumulation of Fibre Breaks under Time Dependent Loads in CFRP Materials of Pressure Vessels N2 - BAM has discovered that the reliability of tested composite pressure vessel will be altered when the loading speed is varied. The ageing of composite materials in general gives negative effect to the structure, however there might be positive effect occurs due to the load redistribution between the fibres. The study on the negative effect of ageing has been compared favourably with the fibre break model from Mines ParisTech. To improve the model's capability, this positive effect should also be implemented. The problem however to evaluate real scale model that might take extensive computation time. The reduced volume method then was proposed to improve the calculation time. The next study is then to check the approach on different loading condition and compare the result with experimental data provided by BAM. T2 - PhD Day 2018 CY - Evry, France DA - 20.06.2018 KW - Fibre Break Accumulation KW - Carbon Fibre Pressure Vessels KW - Time Effect KW - Integral Range PY - 2018 AN - OPUS4-45567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - A few Aspects of the Current Understanding of DPF Materials Thermal and Mechanical Properties N2 - Bi-continuous porous ceramics for filtration applications possess a particularly complicated microstructure, whereby porosity and solid matter are intermingled. Moreover, they very often display a microcrack network, resulting from the strong anisotropy of the microscopic coefficient of thermal expansion (CTE). Mechanical, thermal, and filtration properties, they all strongly depend on the morphology of both solid matter and porosity, and on the degree of microcracking (also, the microcrack density), which is in its turn tightened to the grain size. Recent industrial and academic research has enormously progressed in understanding the microstructure-property-performance relationships existing in these complicated materials: - Using 3D computed tomography (CT) at different resolutions, and several X-ray refraction-based techniques, porosity and pore orientation could be quantitatively evaluated (in the example of cordierite). - Neutron and X-ray Diffraction has been instrumental to disclose a) the non-linear character of the stress-strain response, and b) the negative CTE of these materials, and its consequences on the materials properties; - Analytical and numerical models have been elaborated to rationalize these behaviours in terms of microcracking and microstructural features. Here these results will be reviewed, and a outlook at (some of the) outstanding problems will be given. T2 - HELSMAC CY - Cambridge UK DA - 7.04.2016 KW - Thermal KW - Materials PY - 2016 AN - OPUS4-35752 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Blume, Simon T1 - Femtosecond Laser-induced XUV Spectroscopy (LIXS) for Elemental Analysis N2 - In a typical laser-induced breakdown spectroscopy (LIBS) setup, emissions from collisional excitation of the atoms in the later stages of the plasma are detected and provide information about the elemental fingerprint of the sample. However, precise measurements, in particular quantification efforts, suffer from fluctuations of the intensity of the detected emission lines due to matrix effects and plasma-flicker noise, as well as significant background noise. In contrast, the early stages of the plasma are dominated by electron-ion recombination and Bremsstrahlung, which lead to sharp and intense x-ray emissions with consistent intensity profiles between laser pulses and suppressed background noise, therefore improving the limit of detection, especially for lighter elements. These emissions are detected in laser-induced XUV spectroscopy (LIXS).[1] Introduction of a femtosecond laser (pulse length ~100 fs) to the LIXS setup fundamentally changes the laser energy absorption and ablation process. The laser pulse energy is absorbed and redistributed by multiphoton absorption and inverse Bremsstrahlung and operates on a time frame faster than the plasma formation. Additionally, the plasma formation itself is accelerated leading to signal generation in the XUV-range before generation of the undesired background emissions. Thus, utilization of a femtosecond laser allows for further suppression of broadband emissions from the plasma allowing for sharper separation of the emission lines and improved limit of detection. This work presents the results of the combination of a LIXS setup with a femtosecond laser and assess the capabilities of this system with a model sample of cathode material from a spent lithium-ion battery. T2 - AMACEE 2025 CY - Brno, Czech Republic DA - 26.8.2025 KW - LIXS KW - Femtosecond laser KW - Instrumentation PY - 2025 AN - OPUS4-64118 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Palásti, Dávid jenö T1 - Interferometric sensing in the UV range – Investigation and comparison of the all-reflective spatial heterodyne spectrometer designs N2 - Spatial heterodyne spectrometers (SHS) are optical interferometric devices, working in the UV and visible spectral ranges [1]. The most common SHS setup is similar to the Michelson interferometer, both utilizes a beam splitter in the incoming beam path. In case of the SHS the split beams are not aimed towards orthogonal mirrors, but reflective optical gratings, set under a selected angle. These optical gratings diffract the beams, the direction of every wavelength will depend on the grating constant and the angle of the gratings. The wavefronts belonging to different wavelengths are going to cross each other under a unique angle, resulting in a spatial interference, which is recorded by a digital camera. This relatively compact setup provides high resolution and light throughput, which properties were harnessed for tasks requiring good line separation and/or high sensitivity [2]. However, SHS are only applicable on wavelengths for which an adequate transmissive beam splitter is available like the visible range, but not the far UV. To overcome this limitation, different all-reflective designs were introduced [3]. These instruments utilize symmetric optical gratings for the splitting and recombination of the beams. Although these SHS devices solve the main limitations of the traditional ones, they come with their fair share of drawbacks as well, such as more complex arrangement and the requirement for more delicate tuning. The behaviour of the traditional SHS is well documented [4,5], but in regards of the all-reflective ones we have much less available information. In this current study we utilized computational modelling to predict the behaviour of the all-reflective SH spectrometers, with special attention to the effects of the different alignment errors. Later we utilize this knowledge to fine tune an SHS for sensing (LIBS, Raman) in the UV region. Furthermore, we are introducing two new all-reflective SHS setups and compering them to their older counterparts. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - SHS KW - Spectroscopy PY - 2025 AN - OPUS4-63556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mieller, Björn T1 - Anwendung der Master-Sinter-Kurve bei druckunterstützter Sinterung von Low Temperature Co-Fired Ceramics T2 - DKG-Jahrestagung 2014 CY - Clausthal-Zellerfeld, Germany DA - 2014-03-24 PY - 2014 N1 - Geburtsname von Mieller, Björn: Brandt, B. - Birth name of Mieller, Björn: Brandt, B. AN - OPUS4-30472 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Evaluating Porosity in Cordierite DPF Materials: Advanced X-ray Techniques and New Statistical Anlaysis Methods T2 - CIMTEC 2014 CY - Montecatine Terme, Italy DA - 2014-06-08 PY - 2014 AN - OPUS4-30875 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Analyse von Schädigungsprozessen in Beton - Was leistet die CT? Teil1: Einblick in die Computertomographie N2 - Ein Nachteil der klassischen Durchstrahlungstechnik mit Röntgenstrahlen ist die, in der Abbildung des Untersuchungsobjektes, fehlende Tiefeninformation. Die Anwendung von radiografischen Verfahren, die das Objekt unter zwei oder mehreren Winkelpositionen durchstrahlen, erlauben die Rekonstruktion räumlicher Abbildungen. Dazu zählen Stereoradiografie, Translations- und Rotationslaminographie. Bei der Computertomographie erfolgt die Durchstrahlung unter einem Winkelbereich von 180° oder 360°. Die dabei aufgenommenen Projektionen werden anschließend durch Anwendung der Fourier Transformation und der gefilterten Rückprojektion zu einem 3D-Bilddatensatz rekonstruiert. Verschiedene systembedingte Artefakte, die das Ergebnis negativ beeinflussen können, lassen sich durch geeignete Meß- und Rekonstruktionsparameter, sowie einer nachfolgende Bildverarbeitung eliminieren oder reduzieren. T2 - Summer School im Rahmen des DFG Schwerpunktprogramms 2020 "Zyklische Schädigungsprozesse in Hochleistungsbetonen im Experimental-Virtual-Lab" CY - Hotel Park Soltau, Soltau, Germany DA - 25.06.2018 KW - Computertomographie KW - Durchstrahlungsverfahren KW - Bildverarbeitung KW - Rekonstruktionsverfahren KW - Bildartefakte PY - 2018 AN - OPUS4-45432 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cabeza, Sandra T1 - Characterization of multiphase metal matrix composites by means of CT and neutron diffraction N2 - The present study examines the relationship between the microstructure of multiphase MMC and their damage mechanisms. The matrix AlSi12CuMgNi was combined with 15% vol. Al2O3 (short fibres) and with 7% vol. Al2O3 + 15% vol. SiC (short fibres and whiskers, respectively). The experimental approach encompasses 3D microstructure characterization by means of computed tomography of samples (a) as-received, (b) after heat treatment, and (c) after compression tests at room temperature. The volume fraction of different phases, their distribution, their orientation and the presence of defects and damage are studied. Influence of addition of SiC whiskers on mechanical properties of composite was investigated. Phase-specific load partition analysis for samples with fibre plane parallel to load was perform by using neutron diffraction measurements during in-situ compression. It shows damage in the Si phase, while Al2O3 short fibres carry load without damage until failure. The computed tomography observations confirm the load partition analysis. T2 - World Non Destructive Testing CY - München, Germany DA - 11.06.2016 KW - CT KW - Neutron diffraction KW - Aluminium KW - Composite PY - 2016 AN - OPUS4-38395 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schaupp, Thomas T1 - 3D Charakterisierung wasserstoffunterstüzter Risse in Stahl mittels Synchrotron-Refraktions-CT N2 - Die Fehlertoleranz moderner hochfester Stähle gegenüber Prozessfehlern beim Fügen nimmt stetig ab und erfordert eine immer kritischere Beurteilung der Ergebnisse aus den vorhandenen Prüfverfahren. Deren Aussagekraft ist häufig zu gering und daher muss zum einen das wissenschaftliche Verständnis der Mikrokaltriss-Entstehung in diesen Stählen vertieft werden und zum anderen müssen die Prüfmethoden und Bewertungskriterien angepasst werden. Dies erfordert ein besseres Verständnis insbesondere der Kopplung von Eigenspannungen, Wasserstoffgehalten und der Wirkung äußerer Kräfte auf die Rissentstehung und das Risswachstum. Erstmals soll mittels 3D-Synchrotron-Refraktions-Topographie an der BAMline am BESSY die Rissentstehung in mit Wasserstoff beladenen Zugproben charakterisiert werden. Diese Kenntnisse sollen in weiteren Untersuchungen auf Schweißnähte übertragen werden. T2 - MDDK – Master-, Diplomanden- und Doktorandenkolloquium CY - Universität Magdeburg, Germany DA - 23.06.2016 KW - Duplexstahl KW - Wasserstoffunterstützte Rissbildung KW - Computertomographie KW - Synchrotron-Refraktion PY - 2016 AN - OPUS4-36733 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Evsevleev, Sergei T1 - Stress-induced damage evolution in aluminum matrix composites N2 - Two metal matrix composites, both consisting of a near-eutectic cast AlSi12CuMgNi alloy, one reinforced with 15%vol. Al2O3 short fibers and the other with 7%vol. Al2O3 short fibers + 15%vol. SiC particles were studied. Distribution, orientation, and volume fraction of the different phases was determined by means of synchrotron computed tomography. The load partitioning between phases was investigated by in-situ neutron diffraction compression tests. The internal damage of the eutectic Si phase and Al2O3 fibers after ex-situ compression tests was directly observed in CT reconstructed volumes. Significant debonding between Al-matrix and SiC particles was found. Those observations allowed rationalizing the load transfer among the constituent phases of two different composites. Finally, based on the Maxwell scheme, a micro-mechanical model was utilized for the composite with one and two ceramic reinforcements. The model rationalizes the experimental data, and predicts the evolution of principal stresses in each phase. T2 - The 4th International Congress on 3D Material Science 2018 CY - Elsinore, Denmark DA - 10.06.2018 KW - Computed Tomography KW - Aluminium KW - Metal Matrix Composite KW - Load Partition PY - 2018 AN - OPUS4-45397 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Characterization of Additive Manufacturing Materials at BAM N2 - The combination of tomographic, microstructural data with other experimental techniques and with modeling is paramount, if we want to extract the maximum amount of information on material and component properties. In particular, quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. This logic thread equally holds for industrial and academic research and valorizes expensive experiments such as those carried out at synchrotron sources, which cannot be daily repeated. I will show a few examples of possible use of X-ray tomographic data for quantitative assessment of damage evolution and microstructural properties, as well as for non-destructive testing. Examples of micro-structured inhomogeneous materials will be given, such as Composites, Ceramics, Concrete, and Additively manufactured parts. I will also show how X-ray refraction computed tomography (CT) can be highly complementary to classic absorption CT, being sensitive to internal interfaces. Additionally, I will show how Neutron Diffraction, which is extremely well suited to the study of internal stresses, both residual and under external load, can well be coupled to the microstructural framework gained by CT, allowing understanding the microstructure-property relationships in materials. Finally, I will show that BAM is very active in standardization and certification, including production of Reference Materials and Methods. T2 - Skoltech Determination of the microscopic residual stress CY - Moscow, Russia DA - 20.11.2019 KW - Additive Manufacturing KW - Computed Tomography KW - Neutron Diffraction KW - X-ray refraction techniques KW - Composites PY - 2019 AN - OPUS4-49929 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mieller, Björn T1 - Heißprägen im Grünzustand und Sinterprägen - Zwei Verfahren zur Strukturierung keramischer Folien und Laminate N2 - Prägeverfahren bieten eine interessante Alternative zur Strukturierung keramischer Folien und Laminate. Im Gegensatz zur etablierten Stanz- oder Laserbearbeitung von Einzelfolien sind damit einerseits Strukturtiefen realisierbar, die nicht einem Vielfachen der Einzelfoliendicke entsprechen, andererseits können Strukturierungsgrade erzielt werden, bei denen perforierte Einzelfolien nicht mehr handhabbar sind. Heißprägen grüner Folien und Laminate erfolgt bei Temperaturen um 130 °C mit Metallstempeln. Die plastische Verformung erfolgt zeitabhängig. Dabei sind die Fließeigenschaften des polymeren Binders der Grünfolie maßgeblich für die Konturtreue der Prägung. Randeinzug und Gründichtegradienten um den Eindruck können zu Defekten im Sintergefüge führen. Je nach Sinterverfahren muss die Schwindung der geprägten Struktur berücksichtigt werden, eine Kombination dieses Verfahrens mit zero-shrinkage Techniken ist aber möglich. Sinterprägen stellt eine Erweiterung der Drucksintertechnologie für glaskeramische Komposite dar. Dabei wird ein Pressstempel aus glasartigem Kohlenstoff während des Brandes in die erweichte Glasphase des Komposits gedrückt. Die Abformung erfolgt durch viskosen Fluss der Glasphase. Mit Kenntnis des Dichte- und Viskositätsverlaufs des Werkstoffs kann das Verfahren so gestaltet werden, dass die Pressform konturtreu abgeformt wird. Mittels Sinterprägen lassen sich auch erhabene Strukturen realisieren, wobei diese häufig eine erhöhte Porosität aufweisen. T2 - Herbstsymposium 2016 | Keramische Mehrlagentechnik - Herstellverfahren und Anwendungen CY - Erlangen, Germany DA - 30.11.2016 KW - Folientechnik KW - Keramische Substrate KW - Low temperature co-fired ceramics (LTCC) PY - 2016 AN - OPUS4-38582 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Xue, Boyang T1 - Ultrasound-Assisted Underwater Laser-induced Breakdown Spectroscopy with HighRepetition-Rate μJ-DPSS laser N2 - The elemental analysis of seawater is often critical to the understanding of marinechemistry, marine geochemistry, and the deep-sea ecosystems. Laser-induced breakdownspectroscopy (LIBS) with the advantage of rapid multi-elements detection, has a greatpotential for in-situ elemental analysis of seawater. In practice, it is crucial to create acompact, low cost and power saving instrument for the long-term deep-sea observation. Arecently appeared diode-pumped solid-state (DPSS) laser seems to be a promising candidateas it is both compact and robust. Additionally, its high repetition rate up to hundreds of kHzcan provide a considerable throughput for LIBS analysis. However, the DPSS lasers operateat moderate pulse energies, usually less than one mJ, which cannot sustain stablebreakdowns in bulk water. To ensure stable laser-induced plasmas underwater with such aμJ-DPSS laser, we introduced an ultrasound source to assist the breakdown process. Thephase interface and mass flow generated by the near-field ultrasound can greatly reduce thebreakdown threshold and enhance element-specific emissions. Meanwhile, the highrepetition-rate pulses can also improve the breakdown probability and generate uniqueemission lines originated from the water molecule. We further demonstrate that the highrepetition-rate DPSS laser combined with the Echelle spectrometer can provide effectivequantitative analysis for metal elements in bulk water. T2 - 10th Euro-Mediterranean Symposium on Laser-Induced Breakdown Spectroscopy CY - Brno, Czech Republic DA - 08.09.2019 KW - LIBS KW - Laser induced plasma KW - Plasma modeling KW - Plasma diagnostics KW - Underwater LIBS PY - 2019 AN - OPUS4-49769 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Blume, Simon T1 - Isotopic analysis of lithium via acousto-optically gated high-repetition laser-induced breakdown spectroscopy and spatial heterodyne spectroscopy N2 - Acousto-optically gating the emission signal from a laser-induced breakdown spectroscopy (LIBS) plasma negates some of the line-broadening effects, therefore, improving the signal line shape. However, the remaining influences disallow the differentiation of the contributions of the individual lithium isotopes, even when utilizing a high-resolution spatial heterodyne spectrometer (SHS). Nevertheless, isotopic analysis of lithium with LIBS is still feasible, because lithium exhibits a strong self-absorption dip in the emission signal, which is likewise characterized by the isotopic shift and even benefits from the broad emission lines typically observed in LIBS. The isotopic ration can be resolved from the absorption dip via high-resolution SHS. T2 - SciX 2024 CY - Raleigh, NC, USA DA - 20.10.2024 KW - LIBS KW - SHS KW - Isotopic analysis KW - Lithium PY - 2024 AN - OPUS4-62012 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas T1 - 3D Analysis of transport structures in realistically compressed gas diffusion layer T2 - 6th Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 2014-12-03 PY - 2014 AN - OPUS4-32212 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas T1 - Talbot-Lau interferometry for non-destructive testing T2 - 23. Sitzung des DGZfP-Fachausschusses Zerstörunfreie Materialcharakterisierung CY - Berlin, Germany DA - 2015-11-12 PY - 2015 AN - OPUS4-34823 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mieller, Björn T1 - Druckunterstütztes Sintern von Low Temperature Co-Fired Ceramics: Einfluss der Brennhilfsmittel auf die Oberflächenqualität T2 - DKG-Jahrestagung 2014 CY - Clausthal-Zellerfeld, Germany DA - 2014-03-24 PY - 2014 N1 - Geburtsname von Mieller, Björn: Brandt, B. - Birth name of Mieller, Björn: Brandt, B. AN - OPUS4-30471 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rabe, Torsten T1 - Co-Sinterung von Multilayer-Werkstoffverbunden - Möglichkeiten und Grenzen T2 - DKG-Jahrestagung 2014 CY - Clausthal-Zellerfeld, Germany DA - 2014-03-24 PY - 2014 N1 - Geburtsname von Mieller, Björn: Brandt, B. - Birth name of Mieller, Björn: Brandt, B. AN - OPUS4-30441 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Evaluating Porosity and Properties in Diesel Particulate Filter Ceramics: a Problem to solve with Neutrons and Synchrotron Radiation T2 - Industrie Workshop HZB CY - Berlin, Germany DA - 2013-12-03 PY - 2013 AN - OPUS4-31320 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas T1 - X-ray dark field imaging T2 - 11th European Conference on Non-Destructive Testing CY - Prag, CZ DA - 2014-10-06 PY - 2014 AN - OPUS4-31918 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rabe, Torsten T1 - Prozessbegleitende Prüfung beim Sintern keramischer Schichtverbunde N2 - Die zuverlässige Herstellung von Bauteilen aus Hochleistungskeramik erfordert den Einsatz von prozessbegleitenden Prüfverfahren in allen Fertigungsstufen. Prozessbegleitende Prüfung umfasst sowohl die Bewertung von Ausgangs- und Zwischenprodukten (Pulver, Suspensionen, Grünkörper) als auch die in-situ Überwachung kritischer Fertigungsstufen (Aufbereitung, Formgebung, Entbinderung, Sinterung). Der Arbeitskreis „Prozessbegleitende Prüfverfahren“ im DKG/DGM-Gemeinschaftsausschuss „Hochleistungskeramik“ bietet eine Plattform zum Informationsaustausch über neue Messverfahren und zur Initiierung von Ringversuchen und Referenzmaterialentwicklung. Als aktuelle Beispiele werden zwei applikationsnahe Verfahren zur in-situ Charakterisierung von Geometrieveränderungen (Schwindung, Verformung) an großformatigen keramischen Schichtverbunden vorgestellt. Die Hochtemperatur-3D-Laserprofilometrie ermöglicht die Visualisierung und Quantifizierung der lokalen Verformung keramischer Multilayer während der drucklosen Sinterung. Beobachtet wurden an LTCC-Multilayern starke Verformungen bereits während der Entbinderung und in der Abkühlphase. Das Wissen um zwischenzeitliche Verformungen erweitert das Verständnis über die Ursachen von Defekten in Multilayer-Bauteilen. Die in-situ Messung der Dickenschwindung an realen, großformatigen LTCC-Bauteilen während der druckunterstützten Sinterung wurde erstmals durch die Entwicklung eines LTCC-kompatiblen Drucksinteraggregat mit integriertem Dilatometer ermöglicht. Zusätzlich wurde das Drucksinteraggregat mit einer prozessbegleitende Mess- und Regelungseinrichtung für den Sauerstoffpartialdruck ausgestattet. Durch ein optimiertes Sauerstoffpartialdruckregime konnte an LTCC-Modulen eine qualitätsgefährdende Silberdiffusion aus den Leiterbahnen in das umgebende keramische Dielektrikum drastisch reduziert werden. Das mit einem industriellen Partner entwickelte Drucksinteraggregat eröffnet unikale Möglichkeiten zur Optimierung von Aufheizgeschwindigkeit, Druck und Sinteratmosphäre in allen Phasen des Sinterprozesses. T2 - Werkstoffwoche CY - Dresden, Germany DA - 27.09.2017 KW - In situ Prüfung KW - Keramische Multilayer KW - Laserprofilometrie KW - Drucksintern PY - 2017 AN - OPUS4-42297 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Palásti, Dávid jenö T1 - The effects of the laser pulse profile on the plasma emission properties N2 - Intense laser pulses create plasmas upon radiation on targets, and the properties of such plasmas are generally determined by both the properties of the target and the laser pulse. In terms of laser intensity, the irradiance and even more importantly the fluence are the critical parameters [1]. Since most lasers emit pulses of a constant pulse duration dictated by the design of the resonator and Q-switch, these two parameters are usually used interchangeably in studies. However, with the emergence of fiber laser based light sources [2], which are capable not just to freely tune the pulse duration, but to generate variable and high pulse repetition rates, up to the MHz range, a new and interesting optimization aspect is given to the laser spectroscopy community. In our study a low alloy steel standard sample (BAS 403/1) was investigated using a variable pulse duration and pulse repetition rate MOPA laser with 80W power of  = 1064 nm emission (JPT M7, VONJAN Technology GmbH, Wessling, Germany). In our experiments the laser was set to pulses with low individual energy (0.4 mJ) at 200 kHz pulse repetition rate, while the pulse duration was varied between 50 and 500 ns. The plasma emission was recorded by an LTB Demon spectrometer in several spectral regions, which included iron, chromium and manganese lines. Utilizing the variable pulse duration of this laser source, it was possible to assess the effects of changing the fluence, while the irradiance was kept at the same value. Among the investigated parameters are the emission intensity, peak width and self-absorption characteristics of major and minor components, as well as the plasma temperature. While the effects for the peak intensity are quite well correlated with the fluence, its interplay with other peak parameters appear to be more complicated. T2 - AMACEE 2025 CY - Brno, Czech Republic DA - 26.08.2025 KW - LIBS KW - Fiberlaser KW - Plasma properties PY - 2025 AN - OPUS4-64218 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Riesemeier, Heinrich T1 - Combined synchrotron X-ray and neutron imaging for the characterization of fuel cells T2 - Third Joint BER II and BESSY II Users´ Meeting CY - Berlin, Germany DA - 2011-11-30 PY - 2011 AN - OPUS4-25125 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tötzke, C. T1 - Synchrotron tomographic study on the inhomogeneous compression of gas diffusion layers in fuel cells T2 - 10th Symposium on Fuel Cell and Battery Modelling and Experimental Validation - ModVal 10 CY - Bad Boll, Germany DA - 2013-03-19 PY - 2013 AN - OPUS4-28078 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tötzke, Chr. T1 - 3D Analysis of transport structures in realistically compressed gas diffusion layers T2 - HZB User Meeting 2013 CY - Berlin, Germany DA - 2013-12-04 PY - 2013 AN - OPUS4-17666 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mieller, Björn T1 - Druckgesinterte LTCC-Substrate für die Dünnfilmbeschichtung T2 - DKG-Jahrestagung 2011 CY - Saarbrücken, Germany DA - 2011-03-28 PY - 2011 N1 - Geburtsname von Mieller, Björn: Brandt, B. - Birth name of Mieller, Björn: Brandt, B. AN - OPUS4-23490 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas T1 - Direct X-Ray Refraction of Microstructures T2 - HZB User Meeting CY - Berlin, Germany DA - 2013-12-04 PY - 2013 AN - OPUS4-26611 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Bewertung von Porositätsparametern in Cordierit-Diesel-Partikelfilter-Materialien mit fortgeschrittenen Röntgenverfahren und statistischer Analyse T2 - DGZfP-Jahrestagung 2014 CY - Potsdam, Germany DA - 2014-05-26 PY - 2014 AN - OPUS4-30843 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Evaluating Porosity in Cordierite Diesel Particulate Filter Materials: Advanced X-ray and new Statistical Analysis Methods T2 - 11th European Conference on Non-Destructive Testing CY - Prag, CZ DA - 2014-10-06 PY - 2014 AN - OPUS4-31916 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Bernd R. T1 - Synchrotronstrahlung: verbesserte Refraktions- und Absorptions Mikro-CT für die zerstörungsfreie Materialcharakterisierung T2 - DACH Jahrestagung 2015 CY - Salzburg, Austria DA - 2015-05-11 PY - 2015 AN - OPUS4-33685 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mieller, Björn T1 - New Setter Materials for the Pressure-Assisted Sintering of Low Temperature Co-Fired Ceramics T2 - 14th International Conference of the European Ceramic Society - ECERS 2015 CY - Toledo, Spain DA - 2015-06-21 PY - 2015 N1 - Geburtsname von Mieller, Björn: Brandt, B. - Birth name of Mieller, Björn: Brandt, B. AN - OPUS4-33568 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Plotnikov, Alexei T1 - Application of glow discharge mass spectrometry with "fast flow" source to the determination of impurities in refined magnesium using pressed powder samples T2 - Euroanalysis 2013 CY - Warsaw, Poland DA - 2013-08-25 PY - 2013 N1 - Geburtsname von Mieller, Björn: Brandt, B. - Birth name of Mieller, Björn: Brandt, B. AN - OPUS4-30356 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mieller, Björn T1 - Druckunterstützendes Sintern glaskeramischer Komposite mit Opferfolie aus hexagonalem Bornitrid T2 - 90. Jahrestagung der Deutschen Keramischen Gesellschaft (DKG) CY - Bayreuth, Deutschland DA - 2015-03-15 PY - 2015 N1 - Geburtsname von Mieller, Björn: Brandt, B. - Birth name of Mieller, Björn: Brandt, B. AN - OPUS4-32851 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Evolution of microcrack density under tensile loading in ß-eucryptite T2 - MRS Fall Meeting CY - Boston, MA, USA DA - 2015-11-29 PY - 2015 AN - OPUS4-35169 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Recknagel, Christoph T1 - SENSO JOINT - An innovative sensor for suitable joint design N2 - Inacceptable capability and durability of joint sealing systems but also inadequate traffic performance (noise emission; overrolling comfort) up to traffic safety aspects reflect the still enormous demand for data-based description of concrete pavements performance under heavy loading conditions. Especially the deformation behavior of concrete pavement slabs in the joint region in consideration of new pavement construction types and improved concrete mixtures meanwhile established but also under the steeply rising traffic loads is not sufficiently explored. To create a data basis for advanced design rules, evaluation methods and product standards - and with it to improve quality, durability and finally sustainability of pavements - an innovative 3-D sensor system SENSO JOINT adapted to german roadworking requirements and suitable for heavy-duty operating conditions was developed. The contribution introduced describes the development of an extensive technical solution based on the analysis of decisive loads, interactions and boundary conditions. Based on calibration data, results of laboratory testing and finally field-testing on different concrete pavement construction types the outcome of a multi-level evaluation process shall introduce the potential of the new sensor system. T2 - 9th International Conference on Maintenance and Rehabilitation of Pavements (MAIREPAV 2020) CY - Online meeting DA - 01.07.2020 KW - Concrete pavements KW - Sustainable joint sealing KW - Load quantification KW - innovative measurement technology KW - Field validation KW - Performance design for joint systems PY - 2020 AN - OPUS4-51926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hirsch, Philipp Daniel T1 - Inspection with multisensor laser thermography N2 - The automated testing of complex, highly stressed components requires advanced methods capable of detecting various forms of defects with precision and reliability. In this work we present our approach by combining robotic automation with laser thermography, as a versatile and efficient solution for inspecting intricate geometries under demanding industrial conditions. Central to this approach is the integration of a fiber-coupled laser as a flexible heat source, a high-performance thermal imaging system, an industrial robot, additional visible camera systems, different IR emitters and intelligent signal processing algorithms. This allows, after an initial fully-automated mapping of the part geometry and position that the object under test is thermographically tested for surface or bulk defects. Interferences caused by unideal surface conditions can be corrected for using simultaneously obtained optical images. Finally, all test results can be mapped onto a digital representation of the object leading to a fully digital and machine-readable documentation that can be used for quality assurance. This combination therefore enables accurate defect detection and characterization, overcoming traditional limitations associated with material variability and surface inhomogeneities. The system's adaptability allows for tailored solutions that address real-world challenges, ensuring reliable and repeatable results across diverse applications. The proposed methodology emphasizes the synergy between robotics, active thermography, and advanced data analysis to achieve high levels of precision and automation. This work highlights the potential of these technologies to optimize quality assurance processes and contribute to innovation in various industrial sectors. T2 - Pan-American Conference for Nondestructive Testing (VIII PANNDT) CY - Niagara Falls, Kanada DA - 09.06.2025 KW - ZFP4.0 KW - Automatisation KW - Crack detection KW - Laser KW - Thermography KW - Robot PY - 2025 AN - OPUS4-63646 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Breese, Philipp Peter T1 - Thermographic Methods for In-situ Monitoring of Metal-based Additive Manufacturing Processes N2 - Additive manufacturing (AM) with metals creates new, exciting opportunities for industrial applications. Especially industries with high relevance for the future like transport and energy benefit from optimized designs and novel materials. However, a reliable in-situ quality assurance for metal AM is still missing while process optimization is slow. This directly hinders the huge potential of metal AM technologies. A promising method to counteract this issue is the investigation of the emitted thermal radiation. It is optimal for monitoring and understanding the thermal history of the high-temperature AM process. The thermal history holds virtually all information about the properties and the quality of the manufactured components. The thermal information is also highly valuable for tuning and validating numerical simulations to gather further insights into the process. Despite this importance, the usage of thermal radiation in commercial AM machines is only marginal (like simple pyrometry or long-time exposure for optical tomography (OT) at a single wavelength). Based on this deficit and potential, this work gives an overview of the research in division “8.3 Thermographic Methods” at the Bundesanstalt für Materialforschung und -prüfung (BAM) in Berlin, Germany. Different wavelengths of the thermal radiation are investigated: the visible range (VIS), the short-wave infrared (SWIR), and the mid-wave infrared (MWIR) with their respective optimal field of application. Focus lies on laser powder bed fusion of metals (PBF-LB/M), but directed energy deposition with laser beam (DED-LB/M) is investigated as well. The presented research is performed not only on commercial AM machines, but also on an in-house developed PBF-LB/M research system specifically designed for sensor testing. This ensures an exciting mélange of applied research for industrial applications, and fundamental research for process understanding and validation. Therefore, a crucial contribution to industrial and scientific insights of metal AM is given. T2 - Sim-AM 2025 CY - Pavia, Italy DA - 09.09.2025 KW - Laser powder bed fusion KW - Direct energy deposition KW - Quality assurance KW - Infrared thermography PY - 2025 AN - OPUS4-65391 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Breese, Philipp Peter T1 - Klein, heiß und schnell: Bestimmung von Realtemperaturen in der metallbasierten additiven Fertigung mittels hyperspektraler Thermografie N2 - Die additive Fertigung von Metallen mittels Laser Powder Bed Fusion (PBF LB/M) ermöglicht die Herstellung komplexer Geometrien und die Nutzung neuartiger Legierungen. Die dabei lokal im Prozess auftretenden Temperaturverteilungen beeinflussen maßgeblich die Bauteileigenschaften sowie die Entstehung von Defekten wie bspw. Risse und Poren. Eine quantitative Bestimmung der Realtemperaturen ist daher essenziell für Prozessvalidierung und -vergleich sowie die Qualitätssicherung und das Verständnis der zugrunde liegenden physikalischen Vorgänge. Bisherige thermografische Monitoring-Ansätze liefern jedoch meist nur qualitative Informationen. Hintergrund sind die Herausforderungen gegeben durch den Prozess: kleine Schmelzbäder (< 300 µm), hohe Temperaturen (> 2500 K) und hohe Scangeschwindigkeiten (ca. 1 m/s). Zusammen mit den dynamischen Änderungen des Emissionsgrads u.a. durch Phasenübergänge ergeben sich äußerst schwierige Bedingungen für thermografische Messungen. Um dieser Herausforderung zu begegnen, verfolgen wir einen neuartigen Ansatz zur hyperspektralen Thermografie, der eine simultane Messung der emittierten Strahlung im kurzwelligen Infrarotbereich (1 bis 1,6 µm) entlang einer Linie bei ca. 20 kHz ermöglicht. Durch die Bewegung des Schmelzbades senkrecht durch die Messlinie kann ein typisches Schmelzbad rekonstruiert werden. Die Temperatur-Emissionsgrad-Separation (TES) erlaubt dabei die Bestimmung von Realtemperaturen und Emissionsgraden basierend auf parametrisierten spektralen Emissionsgradfunktionen sowie radiometrischen Kalibrationen. Die Umsetzung erfolgt an der Forschungsmaschine der BAM „SAMMIE“, die speziell für thermografische Messungen am PBF LB/M-Prozess konzipiert wurde. Die Ergebnisse zeigen das Potenzial der hyperspektralen Thermografie zur Erfassung von Realtemperaturen im Prozess. Dies stellt einen wichtigen Schritt zur verbesserten Vergleichbarkeit und Wiederholbarkeit der Fertigung sowie zur Validierung komplexer Simulationen dar. Damit trägt der neuartige Ansatz langfristig zur Erhöhung der Sicherheit und des Verständnisses additiver Fertigungsprozesse bei. T2 - Thermo 25 CY - Garching bei München, Germany DA - 12.11.2025 KW - Laser powder bed fusion KW - Infrarot Thermografie KW - In-situ Monitoring KW - Qualitätssicherung KW - Temperaturmessung PY - 2025 AN - OPUS4-65394 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Spitzer, Stefan T1 - Comparative Study on Standardized Ignition Sources Part 2: Exploration of the Initial Igniting Volume of Standardized Ignition Sources for the Determination of Explosion Characteristics N2 - There are several standardized ignition sources in use for the determination of explosion characteristics of gases, vapors and dusts. In the standards the ignition source is stated, but they vary in stating other characteristics like burning duration, energy or burning volume. Since heat is not visible under normal circumstances a Schlieren-Technique was used to make the full heating volume and not just the flames visible. While an earlier paper of the authors focused on the ignition energy and burning duration of four standardized ignition sources, this paper focuses on the initial igniting volume, the ratio between initial igniting volume and the test-vessel size and other phenomena that were observed with the Schlieren-Technique. T2 - Loss Prevention CY - Prague, Czech Republic DA - 06.06.2022 KW - Ignition source KW - Hybrid Mixtures KW - 20L-sphere PY - 2022 AN - OPUS4-55029 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Spitzer, Stefan A1 - Recknagel, Christoph T1 - INFUSE - SensoJoint Entwicklung neuartiger Sensormethodik N2 - Funktionsschema einer neuartigen Messmethodik zur Ermittlung realer Beanspruchungen von Fugensystemen in hochbeanspruchten Betonfahrbahnbelägen. T2 - Bund-Länder Forschungskolloquium CY - Berlin, Germany DA - 05.07.2017 KW - Dauerhaftigkeit KW - Betonfahrbahndecke KW - Fugenproblematik PY - 2017 AN - OPUS4-41248 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna A1 - Hodoroaba, Vasile-Dan T1 - CUSP inter-laboratory comparisons N2 - In this breakout session first, an introduction is given on the planning and organisation of an inter-laboratory comparison (ILC) under the pre-standardisation plattform VAMAS within the newly formed technical working area TWA 45 Micro and Nano Plastics in the Environment. An update with the ILCs on micro- and nanoplastic performed so far is also given. In the third part, the requirements for a reference materials are presented. The needs from the different H2020 micro- and nanoplastic projects are collected and compiled in an ILC matrix for joint activities as the next steps. T2 - The European Research Cluster to Understand the Health Impact of Micro- and Nanoplastics (CUSP) Launching Event CY - Online meeting DA - 10.06.2021 KW - Microplastic KW - Nanoplastic KW - Inter-laboratory comparison KW - VAMAS KW - Reference material PY - 2021 AN - OPUS4-52808 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhadeliya, Ashok T1 - High Temperature Fatigue Crack Growth in Nickel-Based Alloys Refurbished by Additive Manufacturing and Brazing N2 - Hybrid additive manufacturing plays a crucial role in the restoration of gas turbine blades, where e.g., the damaged blade tip is reconstructed by the additive manufacturing process on the existing blade made of a parent nickel-based alloy. However, inherent process-related defects in additively manufactured material, along with the interface created between the additively manufactured and the cast base material, impact the fatigue crack growth behavior in bi-material components. This study investigates the fatigue crack growth behavior in bi-material specimens of nickel-based alloys, specifically, additively manufactured STAL15 and cast alloy 247DS. The tests were conducted at 950 °C with stress ratios of 0.1 and -1. Metallographic and fractographic investigations were carried out to understand crack growth mechanisms. The results revealed significant retardation in crack growth at the interface. This study highlights the potential contributions of residual stresses and microstructural differences to the observed crack growth retardation phenomenon, along with the conclusion from an earlier study on the effect of yield strength mismatch on crack growth behavior at a perpendicular interface in bi-material specimens. T2 - Superalloys 2024 Conference CY - Champion, PA, USA DA - 08.09.2024 KW - Fatigue crack growth KW - Bi-material structure KW - Nickel-based alloys KW - Additive Manufacturing KW - Brazing PY - 2024 AN - OPUS4-61047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hörenz, Christoph T1 - Improved Sample Preparation for the Analysis of Nanoparticles by Electron Microscopy N2 - Various promising sample preparation procedures aiming to avoid drying artifacts and guarantee homogeneously distributed NP samples for imaging techniques like TEM, SEM or AFM are presented. This involves retarded drying in an environment of high relative humidity as well as spin coating or freeze drying of the sample on the substrate. Depending on the type of the NPs, different techniques are successful in obtaining homogenous sample deposition. Simple drying at ambient conditions often results in heavily agglomerated NPs densely packed in coffee ring traces. Retardation of the drying speed in an environment of high relative humidity, however, yields homogeneous NP deposition in the case of bimodal SiO2 and bimodal gold NP’s. In contrast, a sample of bipyramidal TiO2, heavily agglomerated when commonly dried, is successfully dispersed by spin coating the suspension on the substrate. The analysis of the particle size distribution of the bimodal silica and gold samples yielded number ratios resembling the nominal number ratios. The reliable measurement of the NP concentration of polydisperse samples by electron microscopy, even if relative, is new and of special relevance because up to now only the size of the particles, i.e. the abscissa of the PSD, can be measured reliably. T2 - EMPIR nPSize Training Course "Metrology for Measurement of Nanoparticle Size by Electron Microscopy and Atomic Force Microscopy" CY - Online meeting DA - 27.10.2020 KW - Nanoparticles KW - Particle size distribution KW - Sample peparation KW - Electron microscopy PY - 2020 AN - OPUS4-51716 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jaunich, Matthias T1 - Tieftemperaturverhalten von Elastomerdichtungen - Randbedingung für den Einsatz in Transport- und Lagerbehältern für radioaktive Stoffe T2 - Polymerwissenschaftliches Seminar, BAM CY - Berlin, Germany DA - 2009-06-18 PY - 2009 AN - OPUS4-19568 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zaghdoudi, Maha T1 - Numerical modelling of compression stress relaxation and compression set of elastomer O-rings during aging N2 - Elastomer seals are used in many industrial applications due to their excellent mechanical properties at a wide range of temperatures. Their high versatility and recovery potential under several load conditions make them well suitable for the application in containers designed for transport, storage and/or disposal of radioactive materials. In containers for low and intermediate level radioactive waste, elastomer seals are used as barrier seals, and as auxiliary seals in storage and transportation casks (dual purpose casks) for heat generating radioactive waste, such as spent fuel and high-level waste. While a seal exchange at defined intervals is typical in many conventional applications, it is impossible or at least hard to perform when principles of minimization of radiation exposure have to be considered and prohibit an unnecessary cask handling. An extensive knowledge of the change of the elastomer’s properties during aging and the availability of reliable end-of-lifetime criteria to guarantee the permanent safe enclosure of the radioactive material is mandatory. As BAM is involved in most of the national cask licensing procedures and in the evaluation of cask-related long-term safety issues, great efforts have been already made and are still planned to scientifically support this task. Compression stress relaxation and compression set were identified as key indicators of elastomer long-term performance and quantitatively investigated in comprehensive test programs. Among other representative types of elastomers, specimens made from ethylene propylene diene rubber (EPDM) were tested before, during and after aging to capture the most important of their complex mechanical properties. In the presented study, exemplary results were used to simulate the compression stress relaxation and the compression set of elastomer O-rings during aging. Regarding the influence of temperature, the time temperature superposition principle is applied in the relaxation analysis of elastomer O-rings. The proposed model is implemented in the commercial finite element software ABAQUS/Standard® [1] with a sequential temperature displacement coupling. Numerical results match the experimental compression stress relaxation measurements well. The prediction of compression set values after long-term aging shows a relatively good agreement with the experimental results. Nevertheless, all input parameters derived from the specimen tests, additional assumptions concerning boundary conditions and modeling strategy are discussed with regard to the identified slight discrepancies. The possibility to extend the finite element model to represent the O-ring seal’s ability to recover after a (fast) partial release is taken into account T2 - ASME 2020 Pressure Vessels & Piping Conference (PVP2020) CY - Online meeting DA - 03.08.2020 KW - Stress relaxation KW - Ageing KW - Compression Set KW - O-ring KW - Sequential analysis KW - Simulation PY - 2020 AN - OPUS4-52135 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Charmi, Amir T1 - Virtual-lab-based determination of a macroscopic yield function for additively manufactured parts N2 - This work aims for an yield function description of additively manufactured (AM) parts of S316L steel at the continuum-mechanical macro-scale by means of so-called virtual experiments using a crystal plasticity (CP) model at meso-scale. Additively manufactured parts require the consideration of the specific process-related microstructure, which prevents this material to be macroscopically treated as isotropic, because of crystallographic as well as topological textures. EBSD/CT-Scans from in-house additively manufactured specimen extract the unique microstructural topology which is converted to a representative volume element (RVE) with grain structure and crystal orientations. Crystal plasticity model parameters on this RVE are calibrated and validated by means of mechanical testing under different texture angles. From virtual experiments on this RVE, yield loci under various loading conditions are simulated. The scale bridging from meso- to macro-scale is realised by the identification of the simulated yield loci as a modified anisotropic Barlat-type yield model representation. T2 - The First European Conference on Structural Integrity of Additively Manufactured Materials (ESIAM19) CY - Trondheim, Norway DA - 09.09.2019 KW - Virtual experiments KW - Additive manufacturing KW - Anisotropy KW - Crystal plasticity KW - Scale-bridging PY - 2019 AN - OPUS4-49376 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rockenhäuser, Christian T1 - Microstructural characterisation of ageing and creep of 2618A N2 - Presentation of microstructural characterisation results for alloy 2618A T2 - Projektausschusssitzung mit Industrivertretern der Forschungsvereinigung Verbrennungskraftmaschinen (FVV) CY - Frankfurt a. M., Germany DA - 07.04.2016 KW - Dark-field transmission electron microscopy (DFTEM) KW - 2618A KW - S-Phase KW - Coarsening KW - Microstructure PY - 2016 AN - OPUS4-36705 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jaunich, Matthias T1 - Elastomer seals - overview and development N2 - The talk summarizes the current and future investigations of elastomer seal materials in division 3.4. T2 - IRSN-BAM Symposium Safety of Transport and Storage Packages CY - Online meeting DA - 19.11.2020 KW - Seal KW - Degradation KW - Ageing PY - 2020 AN - OPUS4-51751 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sagradov, Ilja T1 - Long-term tests and numerical simulations on metal seals based on continuous force measurement in compressed state N2 - In Germany, the search for a disposal site for heat-generating radioactive waste will take decades longer than originally assumed. Transport and storage casks must therefore ensure safe containment for extended interim storage periods, possibly over 100 years. In order to maintain the required leak tightness, spring core metal seals with aluminum or silver cladding are used. As sealing force decreases over time, BAM has been conducting tests for over 15 years to prove their long-term reliability. This work - a joint project of BASE and BAM - aims to obtain additional material data using a new device for continuous measurement of compression force over time and temperature for lifetime prediction models and is supported by FEM simulations. Initial tests on aluminum and silver seals have been completed, and first results are presented. T2 - safeND 2025 CY - Berlin, Germany DA - 17.09.2025 KW - Interim storage KW - Metal seal KW - Restoring force PY - 2025 AN - OPUS4-64991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -