TY - CONF A1 - Ramirez Caro, Alejandra A1 - Pauli, Jutta T1 - Study of the hydration of superplasticizer-cement pastes with optical spectroscopy N2 - Chemical admixtures like superplasticizers or stabilizing agents are of ever increasing importance for modern concrete technology. Although such admixtures have meanwhile become common practice in many applications of concrete technology, the understanding of these highly complex systems is still limited and the relevant parameters, which predominantly control the interaction between the superplasticizer and the cement components, have not been identified yet. Optical methods have been successfully used for the analysis and monitoring of the interactions between a broad variety of nanoscale and molecular systems like nanoparticles of various chemical composition and different types of organic ligands or biomolecules. This encouraged us to assess the potential of these methods, and particularly reflectance and fluorescence measurements, for the study of the interactions that occur at the interface between particle or hydrate surfaces and the fluid phase at a very early stage of concrete formation. Special emphasis is dedicated to search for and identify differences between commonly used superplasticizers. Here, we focus on hydration effects using commercial comb shape polycarboxylate ethers (PCEs) with different charge densities, which are known to allow a very low water/cement ratio (w/c of 0.20 or less) while maintaining good workability. Based upon changes of the intensity of the reflectance and fluorescence signal and spectral effects of a dye, acting as optical reporter, a model for the interactions of dye, PCE molecules and cement nanoparticles in the very first phase of cement hydration is derived T2 - Gesellschaft Deutscher Chemiker-Analytische Chemie-Anakon 2017 CY - Tübingen, Germany DA - 03.04.2017 KW - Cement hydration KW - Optical spectroscopy KW - Superplasticizers PY - 2017 AN - OPUS4-39882 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Torge, Manfred T1 - Organic surface coatings on medieval stained glass and microbiological investigation N2 - Mediaeval stained glass has been treated with Polymethylmetacrylate coatings by Kwiatkowski in Poland during the 1950th. Such treated panels were found in the Johannis Church of Toruń (without protective glazing), in the Cathedral of Włocławek (behind a protective glazing), and on glass kept in exhibition cases in the museum of Toruń. Surface coatings have been detected and analyzed. There was no extensive contamination by fungi or bacteria if the glass was either coated or not. T2 - Glass Science in Art and Conservation 2017 CY - Lisbon, Portugal DA - 06.06.2017 KW - Microbiological investigation KW - Medieval stained glass KW - SEM analysis PY - 2017 AN - OPUS4-40573 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Torge, Manfred T1 - SEM and Micro-XRF analysis to investigate stained glass windows N2 - Several restoration projects of stained-glass windows have been performed in Poland since 2010.Chemical analysis of glass samples was performed with SEM/EDX on a FEI ESEM-XL 30, (EDX-EDAX) and with Micro-XRF (M4 Tornado, Bruker).The chemical composition of medieval glass samples and of glass samples of the 19th Century have been determined. T2 - Technart2017 CY - Bilbao, Spain DA - 02.05.2017 KW - SEM KW - Micro-XRF KW - Glass composition PY - 2017 AN - OPUS4-40435 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Additive manufacturing of geopolymers by selective laser curing N2 - Additive manufacturing (3D printing) of ceramics and other materials offers significant advantages compared to conventional production processes for several applications. While ceramics have been extensively investigated in this regard, additive manufacturing of geopolymers have received much less attention to date. In the present contribution we study a ‘standard’ metakaolin-based geopolymer, a fly ash-based geopolymer and a silica-based one-part geopolymer regarding their suitability for additive manufacturing via selective laser curing. Model geometries such as bars and cuboids could be produced by this route. After selective laser curing the specimens were additionally cured at 80 °C for 24 h. The specimens were studied by means of scanning electron microscopy (SEM) and powder X-ray diffraction (XRD). SEM showed that the precursors in all geopolymers had reacted partially and geopolymeric gel had formed. XRD confirmed these results and additionally revealed that the crystalline byproducts (zeolites) in the one-part geopolymer differed from the byproducts observed in conventionally produced samples. This indicates that also the geopolymerization reactions differ between the two synthesis routes. The mechanical strength after selective laser curing and 80 °C-curing appeared to be highest for the metakaolin-based geopolymer. However, SEM also showed that a significant volume of macropores remained in most regions of all specimens, while some regions in the metakaolin-based geopolymer appeared to be significantly denser. These preliminary results demonstrate that selective laser curing offers potential for the production of geopolymers, but more research has to be undertaken to optimize the process. T2 - 92. DKG Jahrestagung CY - Berlin, Germany DA - 19.03.2017 KW - Geopolymers KW - Inorganic polymers KW - Additive manufacturing KW - 3D printing KW - Selective laser curing PY - 2017 AN - OPUS4-39514 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stegemann, Robert T1 - Bewertung der magnetischen Mikrostruktur für die Schadensfrüherkennung N2 - Die Mikrostruktur ferromagnetischer Materialien hat einen maßgeblichen Einfluss auf deren magnetischen Eigenschaften. Gerade bei niedrigen Feldstärken zeigen sich Parameter wie Koerzitivität, Permeabilität und Verlustleistung hoch sensitiv. Wir zeigen am Beispiel des unlegierten Baustahls S235JR, dass die magnetische Mikrostruktur an der Probenoberfläche in hohem Maße mit inhomogenen Dehnungen übereinstimmt. Zur Detektion der Kleinststreufelder verwenden wir speziell designte GMR Sensorik, die Sensitivität (3mV/V/kA/m) mit hoher Ortsauflösung (180 µm) vereint. Infolgedessen können wir auf eine aktive magnetische Anregung verzichten. Wir nutzen allein die sich durch magneto-mechanische Prozesse ausbildende „spontane“ magnetische Mikrostruktur des Materials. Das hervorragende Signal-Rausch-Verhältnis unserer GMR-Sensorik für inhomogene Streufelder erlaubt, schon geringe und lokal abgegrenzte plastische Deformationen in Form und Position reproduzierbar zu visualisieren. Die zugehörigen Signale zeigen die typische Sequenz von erhöhten positiven und negativen Normalkomponenten wie sie bei einer Rissanzeige der aktiven Streuflussprüfung (MFL - Magnetic Flux Leakage) beobachtet wird. Magnetisch kann eine plastische Zone daher als Vorstufe eines Risses betrachtet werden, deren relative Permeabilität für den Riss als Grenzfall zu μr = 1 tendiert. T2 - DGZfP-Jahrestagung CY - Koblenz, Germany DA - 22.05.2017 KW - Baustahl KW - GMR-Sensorik KW - Heterogene plastische Deformation KW - Zugversuch PY - 2017 AN - OPUS4-40375 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiede, Tobias T1 - Residual stress analysis in selective laser melted parts of superalloy IN718 N2 - Additive Manufacturing (AM) by Selective Laser Melting (SLM) offers ample scope for producing geometrically complex parts in comparison to the traditional subtractive manufacturing strategies. Developing during the manufacturing process, residual stresses may limit the application of SLM parts by reducing the load bearing capacity as well as induce unwanted distortion depending on the boundary conditions specified in manufacturing. The present study aims to evaluate the bulk residual stresses in SLM parts by using neutron diffraction measurements performed at E3 line -BER II neutron reactor- of Helmholtz-Zentrum für Materialien und Energie (HZB) Berlin. Together with microstructure characterization and distortion measurements, it is possible to describe the stress state throughout the whole sample. The sample was measured in as-build condition (on a build plate) and after releasing from the build plate. The used material is the nickel based superalloy 718. This alloy is widely used in aerospace and chemical industries due to its superior corrosion and heat resistant properties. Obtained results indicated different residual stress states for each of the transversal, longitudinal and normal component. The normal and transversal component exhibits a rather compressive behavior while the longitudinal was tensile in the center part of the sample and became compressive towards the tip. As expected, the absolute values of all stress components decreased after releasing the sample from the building plate. A surface scan utilizing a coordinate-measuring machine (CMM) allowed us to present top surface distortion before and after releasing. The top surface showed a distortion around ±80µm after releasing. Microstructure evolution in the scanning-building cross-section is largely dominated by columnar grains. In addition, many small random orientated grains are prominent in the regions of a laser overlap during SLM. In summary, for the sample of superalloy 718 manufactured by SLM, a small distortion occurred when removing the sample from the build plate whereby the residual stress state decreases. Moreover, the observed columnar grains in the building direction could give a reason for the lowest stress values in that normal direction. However, the most important parameter controlling the residual stresses is the temperature gradient. Hence, future investigations are planned for a different scan strategy to distribute the laser impact in a more homogenous manner. T2 - 19th HERCULES Specialized Course CY - Grenoble, France DA - 15.05.2017 KW - Additive manufacturing KW - Selective laser melting KW - Residual stresses KW - Distortion KW - Microstructure PY - 2017 AN - OPUS4-40388 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stegemann, Robert T1 - Evaluation magneto-mechanischer Effekte in hochauflösenden Magnetfeldmessungen durch Neutronendiffraktion N2 - Die mechanische Spannung ist ein maßgeblicher Parameter ferromagnetischer Materialien. Wird ein solches Material unter die Curie Temperatur abgekühlt, zerfällt es spontan in nahezu selbstgesättigte magnetische Domänen. Diese Magnetisierung führt gleichzeitig zu einer Verformung der mit ihr gekoppelten Kristallgitter. Ein Effekt der auch reziprok gilt: wird die Gitterverformung durch eine Spannung behindert ändert sich zwangsweise der magnetische Zustand. Man kann annehmen, dass zwischen unterschiedlichen, für sich aber homogen verspannten Werkstoffbereichen, lokale magnetische Streufelder auftreten, weil magneto-mechanische Effekte eine Inkompatibilität der Domänenstruktur induzieren. Bekanntlich bilden sich Spannungsgradienten nach Schweißprozessen durch ungleichmäßigen Wärmeeintrag, thermischer Dehnung, und unterschiedlichen Abkühlraten aus. Unter dieser Prämisse untersuchen wir Wolfram-Inertgas geschweißte Blindnahtproben (250x100x4,8 mm^3) aus einem hypereutektoiden Baustahl. Der Spannungszustand der Proben wurde anhand von Neutronendiffraktometrie (ND) am Instrument E3 am Reaktor BERII (Helmholzzentrum Berlin, HZB) charakterisiert. ND ist ein Referenzverfahren für die quantitative Bestimmung von elastischen Dehnungen in kristallinen Materialien, deren Gitter selbst der Messmaßstab ist. Die Auswertung zeigt hohe Längsspannungen mit lokalen Maxima in Größenordnung von 600 MPa, die von umgebenen Druckspannungszonen kompensiert werden. Zur Detektion der magnetischen Kleinststreufelder verwenden wir speziell designte GMR-Sensorik (GMR - Giant Magneto Resistance), die aufgrund der geringen Größe ihrer aktiven Sensorelemente hohe Ortsauflösung mit Sensitivität vereint. Die Visualisierung der Messergebnisse lässt eine klare magnetische Mikrostruktur der Schweißnähte erkennen, in der die Streufelder lateral in Größenordnung des Erdmagnetfeldes variieren (~50 µT). Wir zeigen durch einen Vergleich beider Messverfahren, dass lokale magnetische Streufeldmaxima in hohem Maße mit den Spannungsgradienten übereinstimmen. T2 - DGZfP-Jahrestagung CY - Koblenz, Germany DA - 22.05.2017 KW - WIG-Blindschweißnaht KW - GMR-Sensorik KW - Neutronendiffraktion KW - Eigenspannungen PY - 2017 AN - OPUS4-40370 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiede, Tobias T1 - Influence of deposition hatch length on residual stress in selective laser melted Inconel 718 N2 - Additive Manufacturing (AM) by Selective Laser Melting (SLM) offers ample scope for producing geometrically complex parts in comparison to the traditional subtractive manufacturing strategies. Developing during the manufacturing process, residual stresses may limit the application of SLM parts by reducing the load bearing capacity as well as induce unwanted distortion depending on the boundary conditions specified in manufacturing. The present study aims to evaluate the bulk residual stresses in SLM parts by using neutron diffraction measurements performed at E3 line -BER II neutron reactor- of Helmholtz-Zentrum für Materialien und Energie (HZB) Berlin. Together with microstructure characterization and distortion measurements, it is possible to describe the stress state throughout the whole sample. The sample was measured in as-build condition (on a build plate) and after releasing from the build plate. The used material is the nickel based superalloy 718. This alloy is widely used in aerospace and chemical industries due to its superior corrosion and heat resistant properties. Obtained results indicated different residual stress states for each of the transversal, longitudinal and normal component. The normal and transversal component exhibits a rather compressive behavior while the longitudinal was tensile in the center part of the sample and became compressive towards the tip. As expected, the absolute values of all stress components decreased after releasing the sample from the building plate. A surface scan utilizing a coordinate-measuring machine (CMM) allowed us to present top surface distortion before and after releasing. The top surface showed a distortion around ±80µm after releasing. Microstructure evolution in the scanning-building cross-section is largely dominated by columnar grains. In addition, many small random orientated grains are prominent in the regions of a laser overlap during SLM. In summary, for the sample of superalloy 718 manufactured by SLM, a small distortion occurred when removing the sample from the build plate whereby the residual stress state decreases. Moreover, the observed columnar grains in the building direction could give a reason for the lowest stress values in that normal direction. However, the most important parameter controlling the residual stresses is the temperature gradient. Hence, future investigations are planned for a different scan strategy to distribute the laser impact in a more homogenous manner. T2 - HZB User Meeting 2017 CY - Berlin, Germany DA - 15.12.2017 KW - AM KW - SLM KW - IN 718 KW - Neutron diffraction KW - Residual stress KW - Hatch length KW - Microstructure PY - 2017 AN - OPUS4-43475 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Röhsler, Andreas T1 - The use of time-of-flight secondary ion mass spectrometry for the investigation of hydrogen-induced effects in austenitic steel AISI 304L N2 - In the course of the energy transformation from fossil fuels to renewable energy sources, the use of hydrogen as fuel and energy storage can play a key role. This presents new challenges to industry and scientific community alike. The storage and transport of hydrogen, which is nowadays mainly realised by austenitic stainless steels, remains problematic. That is due to the degradation of mechanical properties and the possibility of phase transformation by hydrogen diffusion and accumulation. Development of materials and technologies requires a fundamental understanding of these degradation processes. Therefore, studying the behaviour of hydrogen in austenitic steel contributes to an understanding of the damage processes which is crucial for both life assessment and safe use of components in industry and transportation. As one of the few tools that is capable of depicting the distribution of hydrogen in steels, time-of-flight secondary ion mass spectrometry (ToF-SIMS) was conducted after electrochemical charging. To obtain furthermore information about the structural composition and cracking behaviour, electron-backscattered diffraction (EBSD) and scanning electron microscopy (SEM) were performed. Gathered data of chemical composition and topography was treated employing data fusion, thus creating a comprehensive portrait of hydrogen-induced effects in the austenite grade AISI 304L. Specimens were electrochemically charged with deuterium instead of hydrogen. This arises from the difficulties to distinguish between artificially charged hydrogen and traces existing in the material or the rest gas in the analysis chamber. Similar diffusion and permeation behaviour, as well as solubility, allow nonetheless to draw conclusions from the experiments. T2 - SIMS21 CY - Krakau, Poland DA - 11.09.2017 KW - Austenitic stainless steel KW - ToF-SIMS KW - Hydrogen PY - 2017 AN - OPUS4-42315 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Butz, Adam T1 - Experimental and analytical investigation of notched components of a Nickel based superalloy under high temperature cyclic loading N2 - While the increase in use of renewable energy sources is a necessity in times of climate change the use of gas turbines as back-up requires them to be run in a much more flexible manner in order to compensate for side effects like sudden fluctuations of energy generation. The significant changes of stress and temperature levels in turbine blades due to start-up and shut down can cause crack initiation and growth in the blades‘ alloy. The aim of this research project is to identify a model for lifetime prediction for gas turbine components made of a Nickel base superalloy under high temperature with a Focus on stress concentration points such as cooling holes. T2 - HIDA-7 Conference on Life/Crack Assessment & Failures in Industrial Structures, UK CY - Portsmouth, UK DA - 15.05.2017 KW - LCF KW - Gas turbine KW - Service life model PY - 2017 AN - OPUS4-42274 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Saloga, Patrick E. J. T1 - Do non-thermal effects exist? - Microwave-assisted acceleration of silver nanoparticle synthesis and particle growth N2 - Ever since increasing a reaction’s yield while shortening the reaction time is the main objective in synthesis optimization. Microwave reactors meet these demands. In literature however their usage is under discussion due to claims of the existence of non-thermal effects resulting from the microwave radiation. Especially for nano-material syntheses it is of crucial importance to be aware of influences on the reaction pathway. Therefore, we compare ultra-small silver nanoparticles with mean radii of 3 nm, synthesized via conventional and microwave heating. We employed a versatile one-pot polyol synthesis of poly(acrylic acid) (PAA) stabilized silver nanoparticles, which display superior catalytic properties. No microwave specific effects in terms of particle size distribution characteristics, as derived by small-angle X-ray scattering (SAXS) and dynamic light scattering (DLS), are revealed. Due to the microwave reactor’s characteristics of a closed system, syntheses can be carried out at temperatures beyond the solvent’s boiling point. Particle formation was accelerated by a factor of 30 by increasing the reaction temperature from 200 °C to 250 °C. The particle growth process follows a cluster coalescence mechanism. A post-synthetic incubation step at 250 °C induces a further growth of the particles while the size distribution broadens. Thus, utilization of microwave reactors enables an enormous decrease of the reaction time as well as the opportunity of tuning the particles’ size. Possibly, decomposition of the stabilizing ligand at elevated temperatures results in reduced yields. A temperature of 250 °C and a corresponding reaction time of 30 s represent a compromise between short reaction times and high yields. T2 - 5th Nano Today Conference CY - Waikoloa Village, HI, USA DA - 06.12.2017 KW - Microwave synthesis KW - Small-angle scattering KW - Silver nanoparticles PY - 2017 AN - OPUS4-43497 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - On the sliding behavior of PAEK composites in vacuum environment N2 - The tribological behavior of PAEK composites were investigated in air and vacuum environment. Results indicate that the tribological performance of these compounds depends on material compositions, fiber orientation as well as test conditions. In vacuum, very low friction and wear coefficient were obtained at low sliding speed while severe wear occurred at high speed. T2 - The 6th World Tribology Congress - WTC 2017 CY - Beijing, China DA - 17.09.2017 KW - PAEK KW - Sliding performances KW - Vacuum PY - 2017 AN - OPUS4-42447 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tschiche, Harald T1 - Determination of degradation products of thermoplastic polyurethane using fluorescent sensors in a model system N2 - Polyurethanes (PU) are formed by polyaddition reaction between diols and diisocyantes. They can be formed utilizing three building blocks, namely a polyol or long-chain diol, a chain extender or short-chain diol, and a diisocyanate. The derived multi-phase block copolymer has thermoplastic properties and is called thermoplastic PU (TPU). This modular approach allows for a variety of alternations yielding a broad range of structural properties and applications. TPUs are based on three main classes of polyols, i.e. polyethers, polyesters, and polycaprolactones. With these different polyols and the ability of changing the ratio of building blocks a variety of material properties can be obtained thus TPUs find numerous applications in e.g. lightweight construction1, insulation, flame retardants, lacquer and glue, as well as medicine. Linear, isocyanate terminated, polyurethane prepolymers prepared from non-equivalent amounts of diisocyanate such as methylene diphenyl diisocyanate (MDI) attached to a polyol are widely used as precursors of the correspondent polymers. Chain-extending reactions with low molecular weight compounds bearing different amounts of active hydrogens enable both linear and crosslinked polyurethane to be formed. Due to TPUs being used in a broad range of applications facing a variety of stress (e.g. mechanical, hydrolytic, thermal, radiative/UV, as well as its combinations) the complexity of possible degradation mechanism is high. A functional group derived from degradation of the bulk matrix can be detected utilizing a suited fluorogenic sensor molecule. There are several fluorogenic dyes known for the application as sensor for amine groups e.g. fluorescamine, pyrylium dyes, deriving a fluorescent signal upon reaction. T2 - ANAKON 2017 CY - Tübingen, Germany DA - 03.04.2017 KW - Bewitterung KW - Polyurethan KW - Functional group detection KW - Polyurethanes PY - 2017 AN - OPUS4-40262 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kulla, Hannes T1 - In situ investigations of a mechanochemical cocrystal formation by X-ray diffraction for two different milling jar materials N2 - Mechanochemistry has become a valuable method for the synthesis of new materials, especially for pharmaceutical cocrystals. The Advantages of fast reactions in high purity and yield face a lack of understanding the underlying mechanism. Therefore, in situ setups to study mechanochemical reactions have been established. Herein, we present an in situ investigation of the mechanochemical cocrystal formation of pyrazinamide (PZA) with pimelic acid (PM) using synchrotron XRD. Two new polymorphs of PZA:PM (1:1) were synthesized by milling the starting materials in milling jars of different materials. While Form I is only obtained using a steel jar, Form II can be obtained purely in jars made of Perspex. In situ XRD experiments reveal a direct formation of Form II in Perspex and an intermediate formation of Form II in steel jars converting to Form I upon further grinding. Heating experiments and DFT calculations predict that Form II is the thermodynamically more stable polymorph. Therefore, the reaction progress in the steel jar contradicts Ostwald’s rules of stages as the more stable Form II converts into the metastable Form I. Hence, mechanochemistry offers the possibility to synthesize new materials that cannot be obtained using conventional methods. T2 - Adlershofer Forschungsforum 2017 CY - HU-Berlin, Erwin-Schrödinger Zentrum, Germany DA - 10.11.2017 KW - Cocrystal KW - Mechanochemistry KW - Polymorph KW - In situ KW - Milling PY - 2017 AN - OPUS4-42956 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Piedada, F. M. T1 - Polymorphism in Simvastatin: A Single Crystal X-ray Diffraction, Themodynamic, and MDSimulation Study N2 - Simvastatin is a prominent member of the statin family, a class of antilipidemic drugs widely used in the treatment of high plasma cholesterol levels, and thus in the prevention of atherosclerosis and cardiovascular diseases. Simvastatin is typically employed as a solid and it is well known that, in this case, the detection and characterization of polymorphism is of considerable importance. Polymorphs differ by their packing arrangements and also, occasionally, by the conformations of the molecules in the crystal lattice. These structural variations are normally reflected by differences in physical properties, such as solubility and dissolution rate in a given media, which may significantly affect the bioavailability of a drug. The lack of control of polymorphism can, therefore, play havoc with the safe use of a drug. T2 - COST Action CM1402 CY - Lincoln, United Kingdom DA - 26.06.2017 KW - Polymorphism KW - X-ry Diffraction PY - 2017 AN - OPUS4-41252 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nguyen, Thi Yen T1 - Guided crystallization: The influence of solvent and concentration N2 - Theoretical and experimental studies indicate that crystal nucleation can take more complex pathways than expected on the ground of the classical nucleation theory. A direct in situ observation of the different pathways of nucleation from solution is challenging since the paths can be influenced by heterogeneous nucleation sites, such as container walls. The custom-made acoustic levitator using in these experiments regulates the influence that solid surfaces, temperature, and humidity have on the crystallization process. The investigations of the crystallization process of paracetamol were performed with in situ analytical techniques and theoretical simulations to gain a comprehensive insight into processes, occurring intermediates, and required reaction conditions. The targeted choice of the solvent and the concentration enabled the guidance of the pathways, therefore, resulting in the isolation of one desired crystalline structure. T2 - Annual COST meeting CY - Lincoln, United Kingdom DA - 25.06.2017 KW - Crystallization KW - Polymorphism KW - Molecular dynamic simulation KW - Pair distribution function analysis KW - XRD PY - 2017 AN - OPUS4-41111 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Castro, R. A. E. T1 - New cocrystals of bexarotene with pyridinecarboxamide isomers sustained by the acid∙∙∙aromatic nitrogen supramolecular heterosynthon N2 - Pharmaceutical cocrystals are homogenous crystalline structures made up of two or more components in a definite stoichiometric ratio, where at least one of the components in the crystal lattice is an active pharmaceutical ingredient (API).1 Pharmaceutical cocrystals have opened the opportunity for engineering solid-state forms designed to have tailored properties to enhance drug product bioavailability and stability, as well a enhance processability of the solid material inputs in drug product manufacture. In this work the cocrystallization of bexarotene, an approved API by the U.S. Food and Drug Administration that belongs to Biopharmaceutics Classification System Class II (low solubility–high permeability), with pyridine carboxamide isomers (picolinamide, nicotinamide and isonicotinamide) was successfully undertaken. The synthesis was achieved by liquid assisted grinding (LAG) and the solids obtained were characterized by differential scanning calorimetry (DSC), infrared spectroscopy (FTIR-ATR), powder X-ray diffraction (XRPD), single crystal X-ray diffraction (SXD), and polarized light thermomicroscopy (PLTM). For bexarotene: picolinamide and bexarotene:isonicotinamide, 1:1 cocrystals were obtained directly from milling. SXD data of bexarotene:isonicotinamide cocrystal reveal acid∙∙∙aromatic nitrogen supramolecular heterosynthon and that the homosynthon amide∙∙∙amide in isonicotinamide is preserved. The bexarotene:nicotinamide mixtures prepared by ball milling give rise to simple binary solid–liquid phase diagram with an eutectic point, well described by the Schröder-van Laar equation. Melt crystallization of the 1:1 mixture gives rise to a cocrystal for which a complex phase behaviour is observed. T2 - 6th Meeting IAPC CY - Zagreb, Croatia DA - 04.09.2017 KW - Crystalline structure KW - Bexarotene KW - Powder X-ray diffraction KW - Single crystal X-ray diffraction KW - Infrared spectroscopy PY - 2017 AN - OPUS4-41063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nützmann, Kathrin T1 - Depth dependent phase identification of corrosion zones in ferritic alloys by micro-X-ray absorption near edge structure spectroscopy N2 - Ferritic steels with chromium contents up to 13 wt% are used as materials for power plant components as boiler materials (< 2 wt% Cr) and super heater tubes (> 9 wt% Cr). These materials are subject to aggressive corrosion caused by hot gases such as CO2, H2O, O2 and SO2. Especially SO2 causes fatal corrosion even as a minor component. To examine sulfurous corrosion mechanisms, experiments with pure SO2 were conducted. A proper analysis of the material changes requires phase identification and quantification with a high lateral resolution within the corrosion scale. T2 - ANAKON2017 CY - Tübingen, Germany DA - 03.04.2017 KW - Corosion KW - Steel KW - XANES PY - 2017 AN - OPUS4-40415 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Breitfeld, Steffen T1 - High energy ball milling of a new representative of coordination polymers without organofluorine linkers N2 - Metal organic frameworks and coordination polymers play an important role in different fields of applications. Moreover, particularly fluorinated metal-organic frameworks (FMOFs) are in the focus of interest during the last years. In most cases, fluorine is implemented using perfluorinated organic linkers at the synthesis, usually performed by solvothermal synthesis. However, only few examples are known so far where fluorine is coordinated directly to the metal cation. Recently, we reported about mechanochemical syntheses and characterization of fluorine-containing coordination polymers of alkaline earth metals by milling M(OH) (M: Ca, Sr, Ba) with fluorinated benzene dicarboxylic acids 2 and we reported about mechanochemical syntheses of alkaline earth metal fluorides with ammonium fluoride. Now we are reporting about a combination of both synthesis routes. That is the first mechanochemical synthesis of coordination polymers where fluorine is coordinated directly to the metal cation. T2 - Konferenz CY - Berlin, Germany DA - 30.11.2017 KW - Metal organic frameworks KW - Coordination polymer KW - Mechanochemical syntheses KW - Direct fluorine-metal bond KW - Alkaline earth metal PY - 2017 AN - OPUS4-46898 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Li, Wei T1 - Crack propagation in filled and unfilled polymers: Separation of surface energy and irreversible deformation energy N2 - Fiber-reinforced-polymers (FRPs) are in current research focus in the lightweight construction industry, because of their extraordinary characteristics (stiffness and strength-to-density relation). The structure of polymer matrix and the interaction with reinforcement are crucial for optimization of the mechanical and thermal properties of FRPs. Due to the macromolecular chain structure, the mechanical properties of a polymer strongly vary with temperature: Below the glass transition, the chain segments of a polymer are “frozen”. Regarding fracture, the total changed energy during fracture if only dissipates for the generation of the new surfaces. However, in the region of the glass transition, the polymer chain segments start to get “unfrozen”, and the energy is not only required for generating new surfaces, but also for irreversibly deformation. This irreversible deformation is affected by the global temperature and the local temperature near the crack tip, which is affected by the local strain rate and crack propagation velocity. Hence, in this research project, the irreversible deformation of neat and reinforced polymers will be controlled by changing the global temperature as well as the local temperature. With using different fracture experiments, the amount of energy required for creating new surfaces and for the irreversible deformation will be separated. The fracture tests include the conventional tensile test, the macroscopic peel test and the single fiber peel – off test. T2 - PhD Day 2018 of BAM CY - Berlin, Germany DA - 31.05.2018 KW - Crack Propagation KW - Polymer PY - 2018 AN - OPUS4-48471 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina T1 - Dynamics of nanoscopically confined PVME in thin films of an asymmetric PVME/PS blend N2 - In recent years, substantial efforts have been devoted to investigating nanoscopic confinement of polymers, and its effect on glassy dynamics. Broadband Dielectric Spectroscopy (BDS) was used to study the dynamics of ultra-thin films of PVME/PS 50/50 wt% blend, employing a novel nano-structured capacitor sample arrangement. The investigated system shows a complex dynamic behavior. First, an α-relaxation, related to a bulk-like layer was found. Second, an α’-relaxation was observed, characteristic for dynamically asymmetric blends, where the out of equilibrium dynamics is attributed to weakly-cooperative PVME segments relaxing within a frozen environment of PS segments. Thirdly, for thinnest films, an Arrhenius-like process was dominant in the dielectric spectra, indicating localized fluctuations of the segments. Relaxation rates of this process resembled that of the degenerated α-relaxation of the adsorbed layer, found for pure PVME, thus it was assigned accordingly. For thinnest films, this process undergoes a further confinement, due to the topological constraints, introduced by PS. Such multiple confinement effect has not been reported for ultra-thin films of polymer blends, before this study. T2 - Spring Meeting of German Physical Society CY - Berlin, Germany DA - 12.03.2018 KW - Thin polymeric films PY - 2018 AN - OPUS4-44502 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yildirim, Arda T1 - Collective Orientational Order and Phase Behavior of a Discotic Liquid Crystal under Confinement N2 - Discotic liquid crystals (DLCs) are a promising class of soft matter for electronic applications. This is due to their ability to self-organize into columns in a hexagonal columnar mesophase, driven by the overlapping of the π orbitals of their aromatic cores. This leads to a high charge-carrier mobility along the column axis. Previous studies on DLCs showed that their properties, such as phase transition temperatures and enthalpies, are susceptible to nanoconfinement. In this study, 2,3,6,7,10,11 hexakis[hexyloxy] triphenylene (HAT6) was confined into parallel aligned cylindrical nanopores of anodic aluminum oxide (AAO) membranes by melt infiltration. Furthermore, the pore surfaces of a series of membranes were chemically modified, resulting in a more hydrophobic pore surface than the unmodified ones. Collective orientational order and phase behavior of HAT6 confined into modified and unmodified nanopores of AAO were investigated by broadband dielectric spectroscopy and differential scanning calorimetry respectively. T2 - Spring Meeting of German Physical Society CY - Berlin, Germany DA - 12.03.2018 KW - Discotic Liquid Crystals PY - 2018 AN - OPUS4-44506 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Omara, Shereen T1 - Structure−property relationships of hyperbranched polyamine ester/Ka-DCA nanocomposites N2 - Hyperbranched polyamine ester (HPAE)/ kaolinite nanocomposites were papered via an ex situ (solution-based) method. The kaolinite has been modified by dodecylamine (DCA). SAXS measurements revealed that the Ka interlayer space increased from 0.71 to 3.6 nm-1. A partly exfoliated structure of the HPA/Ka-DCA nanocomposites was proved by SAXS and TEM. By a combination of BDS and SHS, the relaxation properties of the nanocomposites were investigated in dependence on frequency and temperature. The activation energies of γ-relaxation for the nanocomposites were lower than the values found for the pure HPAE. The segmental dynamics (α- relaxation) was found to be screened out by the conductivity contribution. While it is retrieved by SHS employing AC-chip calorimetry. A systematic change of the dynamic glass transition estimated by AC-chip calorimetry was observed, which is in agreement with a behavior expected for a confined sample. The confinement effect of the Ka-DCA nanofillers reduces the glass transition temperature Tg and enhances, meanwhile, the electrical conductivity of the polymer. By comparing the temperature dependence of the dynamic glass transition measured with SHS and that of the dc conductivity measured by dielectric spectroscopy, a decoupling in their temperature dependencies was found. With increasing concentration of the nanofiller, which results in a stronger glass-formation behavior, this decoupling becomes weaker. T2 - Spring Meeting of German Physical Society CY - Berlin, Germany DA - 12.03.2018 KW - Nanocomposites PY - 2018 AN - OPUS4-44522 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gawek, Marcel T1 - Growth Kinetics and Molecular Mobility of Irreversibly Adsorbed Layers in Thin Polymer Films N2 - In well-annealed thin polymer films, with non-repulsive polymer/substrate interactions, an irreversibly adsorbed layer is expected to form. These adsorbed layers have shown great potential for technological applications. However, their growth kinetics and molecular dynamics are still not fully understood. This is partially due to the hard accessibility of these layers in thin films. Here, the irreversibly adsorbed layers of homopolymer thin films are revealed by solvent-leaching experiments. First, the growth kinetics of these layers is investigated as a function of annealing times and original film thickness. The thickness, topography and quality of the adsorbed layer is controlled with Atomic Force Microscopy (AFM). Secondly, the molecular mobility of the adsorbed layer is investigated with Broadband Dielectric Spectroscopy (BDS). A recently developed nanostructured capacitor is employed to measure the adsorbed layers with a free surface layer. The results are quantitatively compared and discussed with respect to recently published work. T2 - Spring Meeting of German Physical Society CY - Berlin, Germany DA - 12.03.2018 KW - Thin polymeric films KW - Dielectric spectroscopy PY - 2018 AN - OPUS4-44489 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kauss, N. A1 - Rosemann, Paul T1 - Age-hardening behaviour, microstructure and corrosion resistance of the copper alloyed stainless steel 1.4542 N2 - The copper alloyed stainless steel 1.4542 (X5CrNiCuNb16-4) is used in different areas due to its good mechanical properties and corrosion resistance. Strength and corrosion resistance can be adjusted by the heat treatment, which is of importance for the application of this alloy. The mechanical properties (strength and hardness) are attributed to the dispersive precipitation of the copper rich ε–Phase. The additional precipitation of chromi-um carbides can reduce the corrosion resistance. Different ageing states were produced to investigate the precipitation behaviour with various methods. Furthermore, the influence of cold-rolling on the precipitation behaviour was studied in comparison to a solution annealed state without deformation. The microstructure was studied by SEM and the variations of hardness and magnetic proportion were characterised. The electrochemical potentiodynamic reactivation (EPR) was used to determine the corrosion resistance and detect chromium depletion in all heat-treated states. The results show that a work hard-ening accelerates the precipitation rate, while ageing at 600 °C reduces the corrosion resistance due to chromium depletion. T2 - 20. Werkstofftechnischen Kolloquium CY - Chemnitz, Germany DA - 14.03.2018 KW - Corrosion KW - Heat treatment KW - Stainless steel KW - Corrosion resistance KW - EPR KW - Corrosion testing PY - 2018 AN - OPUS4-44553 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kern, Simon T1 - Novel Flow Cell Designs for Process Monitoring with Compact NMR Spectroscopy N2 - Compact nuclear magnetic resonance (NMR) instruments make NMR spectroscopy and relaxometry accessible in industrial and harsh environments for reaction characterization and process control. Robust field integration of NMR systems have to face explosion protection or integration into process control systems with short set-up times. This paves the way for industrial automation in real process environments. The design of failsafe, temperature and pressure resistant flow through cells along with their NMR-specific requirements is an essential cornerstone to enter industrial production plants and fulfill explosion safety requirements. Additionally, if fast reactions are monitored, suitable mixing devices need to be placed in close vicinity to the measuring volume to mix the reactants properly. NMR-specific requirements aim at full quantitative pre-magnetization and acquisition with maximum sensitivity while reducing sample transfer times and dwell-times. All parameters are individually dependent on the applied NMR instrument. Luckily, an increasing number of applications are reported together with an increasing variety of commercial equipment. However, these contributions have to be reviewed thoroughly. The performance of sample flow cells commonly used in online analytics and especially for low-field NMR spectroscopy was experimentally and theoretically investigated by 1H-NMR experiments and numerical simulations. Especially, the applicability of 3D printed zirconium dioxide for innovative flow cell designs was of interest. Here, we demonstrate and discuss an automated test method to determine the critical parameters of flow through cells for quantitative online NMR spectroscopy. The setup is based on randomized setpoints of flow rates in order to reduce temperature related effects. Five flow cells and tubing were assessed and compared for high-field as well as low-field NMR spectrometers. T2 - Practical Applications of NMR in Industry Conference ​(PANIC) 2018 CY - La Jolla, California, USA DA - 04.03.2018 KW - Process Monitoring KW - Process Control KW - Flow Cell KW - Online NMR Spectroscopy KW - Additive Manufacturing KW - CONSENS PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-444364 N1 - Geburtsname von Bornemann-Pfeiffer, Martin: Bornemann, M. - Birth name of Bornemann-Pfeiffer, Martin: Bornemann, M. AN - OPUS4-44436 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lange, Thorid T1 - HARFE: Haftfestigkeit Reproduzierbarkeit Festigkeit „Nanoskalige Haftvermittler zur Erhöhung der Haft- bzw. Klebfestigkeit unter Verwendung von ALD-Hybridprozessen“ N2 - Das Poster „HARFE: Haftfestigkeit Reproduzierbarkeit Festigkeit“ widmet sich den nanoskaligen Haftvermittlern zur Erhöhung der Haft- bzw. Klebfestigkeit unter Verwendung von ALD-Hybridprozessen. T2 - Netzwerksymposium “Schützen und Veredeln von Oberflächen”, Wildau CY - TH Wildau, Germany DA - 01.03.2018 KW - Verbundfestigkeit KW - Oberflächenenergie KW - ALD-Beschichtung PY - 2018 AN - OPUS4-44399 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haferkamp, Sebastian T1 - In situ investigation of mechanochemical Knoevenagel condensations of benzaldehyde derivates N2 - Mechanochemistry is known for short reaction times, nearly quantitative conversions, and decreasing amount of solvents. Among organic syntheses, the Knoevenagel condensation is an important C-C bond forming reaction. We investigated the reaction of benzaldehyde derivates (nitro- and fluoro-derivates) with malononitrile syntheses by a combination of different in situ investigation techniques. T2 - BESSY II User Meeting CY - Berlin, Germany DA - 05.12.2018 KW - Mechanochemistry KW - In situ PY - 2018 AN - OPUS4-46997 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pfretzschner, Beate T1 - Characterization of texture in SLM IN 718 samples using monochromatic neutron radiography N2 - Additive Manufacturing (AM) offers the opportunity to produce easier geometrically complex parts compared to traditional production technologies. An important AM technology for metals is selective laser melting (SLM) where a part is produced by melting and solidifying powder in layers. This technique is known to cause a pronounced texture in the produced AM products due to the specific heat flow and the associated solidification of the material during SLM deposition. In order to evaluate the influence of the deposition hatch length during SLM of nickel based superalloy Inconel 718 samples on the texture and in order to identify any preferred crystallographic direction, we performed monochromatic neutron radiography scans (using wavelength from 1.6 Å to 4.4 Å, step size 0.05 Å) to image the samples while rotating it through 90°. Samples produced with short hatch length showed fine textured columnar grains oriented along the sample building direction in high-resolution radiographs. Whereas processing the sample using a ten-fold longer hatch length reduced the texture. The neutron radiographic experiments were accompanied by scanning electron microscopy including electron back-scattered diffraction to visualize and verify the microstructure and texture. T2 - German Conference for Research with Synchrotron Radiation, Neutrons and Ion Beams at Large Facilities CY - Garching, Germany DA - 17.09.2018 KW - Bragg-edge KW - Neutron KW - Texture KW - Additive manufacturing PY - 2018 AN - OPUS4-47260 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kratzig, Andreas T1 - Interaction of Reactive Components in CO2 Streams with Transport Pipeline Steel X70 N2 - In context of CLUSTER project, impacts of impurities (SO2, NO2, O2, CO, H2S, H2, N2, Ar and H2O) in CO2 streams captured from different sources in a regional cluster on transport, injection and storage were investigated. Corrosion studies of oxidizing, reductive or mixed atmospheres towards transport pipeline steel X70 were carried out applying high pressure (10 MPa) at low temperatures (278 K or 313 K). T2 - GHGT-14 Conference CY - Melbourne, Australia DA - 22.10.2018 KW - Carbon capture KW - CCS KW - Carbon dioxide KW - Corrosion PY - 2018 AN - OPUS4-47017 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sommer, Konstantin T1 - Microstructure characterization of additive produced parts N2 - Due to the advantages of additive manufacturing (AM), it has been increasingly integrated into many industrial sectors. The application of AM materials for safety-critical parts requires the detailed knowledge about their microstructure stability under thermo-mechanical or mechanical load and knowledge on ageing process mechanisms. Ageing processes are characterized by change of the material microstructure that is to be initially investigated. This work deals with the Investigation of 316L stainless steel manufactured by selective laser melting (SLM). Describing Parameters must be defined and applied on the microstructure of these materials in their initial state and after loads were applied. The findings of this work form the basis for the investigation of AM material ageing. T2 - FEMS Junior EUROMAT 2018 CY - Budapest, Hungary DA - 08.07.2018 KW - Additive manufacturing KW - Selective laser melting KW - 316L KW - Material characterization KW - Microstructure PY - 2018 AN - OPUS4-47176 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kiefer, P. T1 - Statistical analysis of Vickers induced subcritical crack growth in soda-lime silicate glasses N2 - Studies on Vickers induced subcritical crack growth are controversially discussed since the stresses that drive the crack growth are distributed three dimensionally within the material and cannot be retraced by available methods. Hence, empirical approaches are used to calculate mechanical material parameters such as the stress intensity factor KI. However, the results of these approaches show large deviations from those measured by standardized techniques such as double cantilever beam (DCB) or double cleavage drilled compression (DCDC). Yet, small specimen sizes and low specimen quantities can prevent the execution of DCB and DCDC measurements. Here we present an approach that is based on a statistical analysis of Vickers induced radial cracks. For this purpose more than 150 single radial cracks were analyzed. The cracks were generated in a commercial soda-lime silicate glass. The experiments were performed in a glovebox purged with dry nitrogen gas to minimize the influence of atmospheric water on crack growth. The temporally resolved evolution of the radial cracks was monitored in-situ using an inverted microscope equipped with a camera system directly below the Vickers indenter. An automated image analysis software was used to determine the crack length over time. The data show that the crack propagation and thereby the crack velocities are not uniformly but statistically distributed. These findings allow, using the statistical mean value of the distributions in combination with DCB data, a precise formulation of KI for each measured crack length. T2 - 92nd Annual Meeting of the German Society of Glass Technology in Conjunction with the Annual Meetings of the Czech Glass Society & the Slovak Glass Society CY - Bayreuth, Germany DA - 28.05.2018 KW - Crack growth KW - Soda-lime silicate glass KW - Vickers PY - 2018 AN - OPUS4-45703 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koclęga, Damian A1 - Radziszewska, A. A1 - Kranzmann, Axel A1 - Dymek, S. T1 - Microstructure characterization of the Inconel 686 clad layer after high-temperature corrosion tests in aggressive gases and ashes N2 - The Ni-Cr-Mo-W alloy is characterized by the excellent high-temperature corrosion resistance, good strength and ability to work in aggressive environments. To protect the surface of the substrate 13CrMo4-5 steel against aggressive environments the Inconel 686 as clad layer was used. The corrosion process was performed in oxidizing mixture of gases like O2, COx, SOx. The second part of corrosion Experiment concerned the corrosion test of the coating in reducing atmosphere of the specified gases with ashes, which contained e.g. Na, Cl, Ca, Si, C, Fe, Al. T2 - Junior EUROMAT 2018 CY - Budapest, Hungary DA - 08.07.2018 KW - Laser Cladding KW - Inconel 686 KW - High temperature corrosion KW - Aggressive environement KW - Material oxidation PY - 2018 AN - OPUS4-45627 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Even, Morgane T1 - Investigations on emission properties of VOCs from consumer products made of polymers N2 - There is a need for an assessment of the emission properties of volatile organic compounds (VOCs) from consumer products. A method comparison was carried out to evaluate adapted and cost-effective procedures for such items. Smaller and automated emission chambers de-picted similar kinetics compared to a 203 L standard chamber. Toy samples made of PVC (Polyvinyl chloride) emitted more VOCs compared to other tested polymeric products. The emissions from 2 selected samples were studied to allow an evaluation of the resulting room concentration and external exposure of a child. Obtained concentrations were not of concern. T2 - Conference on Indoor Air 2018 CY - Philadelphia, USA DA - 22.07.2018 KW - Emission chamber testing KW - Volatile organic compounds KW - Consumer articles PY - 2018 AN - OPUS4-45662 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kauss, N. A1 - Heyn, A. A1 - Rosemann, Paul T1 - How to Detect Sensitivity on Aged Lean-Duplex Stainless Steel With Electrochemical Methods N2 - The influence of isothermal ageing on microstructure, sensitisation and pitting corrosion resistance of the lean duplex stainless steel (LDSS) X2CrNiN23-4 was investigated with various electrochemical methods. The aging at 600 °C (from 0.1 h up to 20 h) lead to the formation of precipitations at the ferrite-ferrite (α/α) and ferrite-austenite (α/γ) grain boundaries, inducing sensitisation due to chromium depletion. The degree of sensitisation was evaluated with the double loop electrochemical potentiokinetic reactivation method (DL-EPR) according to ASTM G108 and correlated with critical pitting potentials (Epit) as well as critical pitting temperature (CPT) measured in an electrolyte according to ASTM G48 using electrochemical noise. Up to an ageing time of 1 h, the sensitisation did rise significantly, stabilising at a nearly constant level with a slight drop at 20 h. This behaviour correlated perfectly with the potentiodynamically determined pitting potentials Epit and sensitisation. The CPT showed a higher sensitivity at short ageing times compared to the DL-EPR and Epit. Finally, the KorroPad method was applied to visualise the sensitisation induced reduction of pitting corrosion resistance. The “KorroPad” is an agar-based gel-electrolyte containing 0.1 mol/l sodium chloride (NaCl) and 0.1 mol/l potassium ferricyanide III (K3[Fe(CN)6]), invented at the Federal Institute of Materials Research and Testing in Berlin (Germany) to detect surfaces of stainless steel prone to pitting corrosion. The standard configuration of the KorroPad showed no differentiation for the various aging conditions. Increasing the concentration of both NaCl and potassium ferrocyanide III to 0.5 M shifts the detection limit of the KorroPad method to stainless steels with higher corrosion resistance, producing the same trends detected by standard electrochemical pitting corrosion values (Epit, CPT) and sensitisation (DL-EPR). By that, the KorroPad method was successfully adjusted to the lean-duplex stainless steel X2CrNiN23-4, enabling short-time testing to detect sensitization. T2 - Electrochemical Methods in Corrosion Research 2018 CY - Cambridge, UK DA - 22.07.2018 KW - Corrosion testing KW - Duplex stainless steels KW - Corrosion KW - KorroPad KW - Pitting corrosion KW - EPR KW - Electrochemical noise KW - Stainless steel PY - 2018 AN - OPUS4-45615 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wilke, Olaf T1 - Comparison of Formaldehyde Concentrations in Emission Test Chambers Using EN 717-1 and EN 16516 N2 - For many years EN 717-1 (Wood-based panels - Determination of formaldehyde release - Part 1: Formaldehyde emission by the chamber method) is the standard for formaldehyde emission testing of wooden boards. In 2017 EN 16516 (Construction products - Assessment of release of dangerous substances - Determination of emissions into indoor air) was published as a new harmonised standard for the emission testing of construction products. Because test chamber conditions are different, both standards give different concentrations for formaldehyde. For the determination of a conversion factor four test series were set up with different wooden boards. T2 - Conference on Indoor Air CY - Philadelphia, PA, USA DA - 22.07.2018 KW - Loading factor KW - Construction products KW - European standard KW - Air exchange rate PY - 2018 AN - OPUS4-45631 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rosemann, Paul A1 - Kauss, N. A1 - Müller, C. A1 - Halle, T. T1 - Heat treatment and corrosion resistance of cutlery N2 - Hardness and pitting corrosion resistance are the major quality criteria of cutlery. Both are achieved by the heat treatment (austenitization, quenching and tempering) of the normally used martensitic stainless steels. The established quality control method regarding the pitting corrosion resistance is an alternating immersion test in 1 % NaCl solution at 60 °C according to DIN EN ISO 8442. This standard test shows a high deviation, which limits any optimization of the heat treatment process. New approaches for corrosion testing of martensitic stainless-steels were developed and used in the last years to connect the weak pitting corrosion resistance of martensitic stainless-steels with the phenomenon of chromium depletion. The tempering temperatures used in the industrial heat treatment of cutlery are too low to explain the appearance of chromium depletion. For this reason, a systematic investigation of three heat treatment parameters (austenitization time, cooling speed and tempering temperature) were performed on the martensitic stainless-steels X50CrMoV15 (1.4116) to detect their contribution to chromium depletion. The electrochemical potentiodynamic reactivation (EPR), which is very sensitive to any change of the microstructure, was used to quantify the degree of chromium depletion. The KorroPad indicator-test was applied to correlate low pitting corrosion resistance to the presence of chromium depletion. The results of all investigations allow conclusions about the very small process window, which is necessary to achieve cutlery with high pitting corrosion resistance. T2 - EUROCORR 2018 CY - Krakow, Poland DA - 09.09.2018 KW - Corrosion KW - KorroPad KW - Stainless steel KW - Corrosion resistance KW - Heat treatment KW - EPR KW - Pitting corrosion KW - Martensitic stainless steels KW - REM PY - 2018 AN - OPUS4-45952 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rosemann, Paul A1 - Kauss, N. T1 - Visualization of material-related susceptibility to pitting corrosion with the “KorroPad” indicator test N2 - The KorroPad indicator test was invented at the Federal Institute for Materials Research and Testing to detect stainless-steel surfaces susceptible to pitting corrosion. The KorroPad indicator test is thus an interesting alternative for manufacturers, processors, users and researchers to time consuming exposition experiments and complex electrochemical investigations, which are normally used to reveal surface-related processing errors resulting in reduced pitting corrosion resistance. Furthermore, the KorroPad indicator test can be used to visualize alloy- and microstructure-related factors causing susceptibility to pitting corrosion. The detection limit of the KorroPad indicator test was characterized in this work using reference alloys with different chromium content (5 % to 18 %). The alloy-specific detection limit was shifted successfully to higher chromium content by increasing the concentrations of NaCl and K3[Fe(CN)6]. The modified KorroPads can now be used to establish an alloy-specific quality control regarding the pitting corrosion resistance of different stainless steel grades. T2 - EUROCORR CY - Krakow, Poland DA - 09.09.2018 KW - Corrosion KW - KorroPad KW - Stainless steel KW - Corrosion resistance KW - Corrosion testing KW - Pitting corrosion PY - 2018 AN - OPUS4-45953 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rosemann, Paul A1 - Müller, C. A1 - Roßberg, S. A1 - Pensel, P. A1 - Halle, T. A1 - Burkert, A. T1 - Precipitation behavior and corrosion resistance of nickel-free, high-nitrogen austenitic stainless steels N2 - Nickel-free, nitrogen alloyed austenitic stainless-steels, with about 19 wt.-% Mn and 0,8 wt. % N, are an interesting alternative to classic CrNi austenitic stainless steels due to their superior mechanical properties (Rm > 900 MPa, A5 > 50 %, Av > 350 J) in the solution annealed condition. The formation of chromium-rich nitrides during suboptimal heat treatment, processing or application leads to an inhomogeneous distribution of alloying elements in the microstructure, which reduces the corrosion resistance. Consequently, an accurate knowledge of the sensitization behavior is indispensable for the use of nickel-free, high-nitrogen austenitic stainless steels. The relationship between artificial aging, phase formation and corrosion resistance was investigated on the alloys X8CrMnN18-19 (1.3815) and X8CrMnMoN18-19-2 (1.4456), both alloyed with 0,8 wt.-% Nitrogen, in the present work. The microstructural evolution was studied by LM and SEM while the corrosion resistance was characterized with the electrochemical potentiodynamic reactivation (EPR) and the KorroPad indicator-test. Both alloys showed increased corrosion susceptibility within critical aging parameters. Finally, a sensitization diagram was described successfully for both alloys showing the positive effect of molybdenum. T2 - EUROCORR 2018 CY - Krakow, Poland DA - 09.09.2018 KW - Corrosion KW - KorroPad KW - Stainless steel KW - Corrosion resistance KW - Heat treatment KW - ThermoCalc KW - Pitting corrosion KW - Nitrogen PY - 2018 AN - OPUS4-45954 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kauss, N. A1 - Rosemann, Paul A1 - Halle, T. T1 - Age-hardening behaviour, microstructure and corrosion resistance of the copper alloyed stainless steel 1.4542 N2 - The copper alloyed stainless steel 1.4542 (X5CrNiCuNb16-4) is used in different areas due to its good mechanical properties and corrosion resistance. Strength and corrosion re-sistance can be adjusted by the heat treatment, which is of importance for the application of this alloy. The mechanical properties (strength and hardness) are attributed to the dispersive precipitation of the copper rich ε–Phase. The additional precipitation of chromium carbides can reduce the corrosion resistance. Different ageing states were produced to investigate the precipitation behaviour with various methods. Furthermore, the influence of cold-rolling on the precipitation behaviour was studied in comparison to a solution annealed state without deformation. The microstructure was studied by SEM and the variations of hardness and magnetic proportion were characterised. The electrochemical potentiodynamic reactivation (EPR) was used to determine the corrosion resistance and detect chromium depletion in all heat-treated states. The results show that a work hardening accelerates the precipitation rate, while ageing at 600 °C reduces the corrosion re-sistance due to chromium depletion. T2 - EUROCORR 2018 CY - Krakow, Poland DA - 09.09.2018 KW - Corrosion KW - Stainless steel KW - Corrosion resistance KW - EPR KW - Corrosion testing KW - Heat treatment KW - ThermoCalc KW - REM KW - Martensitic stainless steels PY - 2018 AN - OPUS4-45955 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yildirim, Arda T1 - Collective Orientational Order and Phase Behavior of a Discotic Liquid Crystal under Confinement N2 - Discotic liquid crystals (DLCs) are a promising class of soft matter for electronic applications. This is due to their ability to self-organize into columns in a hexagonal columnar mesophase, driven by the overlapping of the π orbitals of their aromatic cores. This leads to a high charge-carrier mobility along the column axis. Embedding liquid crystals into nanopores of anodic aluminum oxide (AAO) results in a 2D nanoconfinement of these materials. This confinement affects their properties, compared to the bulk, such as phase transition temperatures and enthalpies, molecular mobility, and crystallization. In this study, 2,3,6,7,10,11 hexakis[hexyloxy] triphenylene (HAT6) was confined into parallel aligned cylindrical nanopores of AAO membranes by melt infiltration. The membrane as confining hosts used have varying pore diameters, from 10 nm to 160 nm, covering a broad pore size range, thus, a better understanding of the confinement effect on phase behavior and molecular configuration in the pores. Furthermore, it is aimed to obtain axial ordering or to increase degree of axial ordering by chemically modifying the surfaces of the pores. Therefore, the pore surfaces the membranes were chemically modified, resulting in a more hydrophobic pore surface than the unmodified ones. The phase behavior was explored by a power-compensated DSC allowing the detecting of small changes in the phase behavior. In the literature, dielectric spectroscopy was demonstrated as a method to monitor molecular order inside the pores. Here, we also investigate the collective orientational order, corresponding to dominating molecular ordering, by dielectric spectroscopy. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussles, Belgium DA - 26.08.2018 KW - Confined Columnar Liquid Crystals PY - 2018 AN - OPUS4-45916 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina T1 - Molecular dynamics of an asymmetric PVME/PS Blend investigated by broadband dielectric and specific heat spectroscopy N2 - Over the past decades research on the molecular dynamics of miscible polymer blends are of topical interest in the literature, in an attempt to understand the segmental mobilty of individual components, as it is affected by blending. In general, miscible polymer blends exhibit a complex behavior of the molecular mobility. For an A/B blend the relaxation times of component A and component B are affected by the spatial local compositional heterogeneity, present in binary systems on a microscopic level, regardless of the macroscopic homogeneity. Here, a combination of broadband dielectric and specific heat spectroscopy was employed to study the dynamically asymmetric PVME/PS blend with seven different compositions, focusing on samples with high PS contents. Considering that PS is dielectrically invisible, BDS is a powerful technique to study the response of PVME, as it is affected by PS segments. In this work the well-known binary relaxation times distribution of PVME in a blend, originating from the spatial local heterogeneity, was studied over ten decades in frequency, for the first time in literature. Secondly, one of the detected processes, α’-relaxation, shows a crossover from high-temperature behavior (system in equilibrium) towards a low temperature regime, where PS undergoes the thermal glass transition, resulting in confined segmental dynamics of PVME within a frozen network of PS. Here, we introduce a precise mathematical tool to distinguish between the temperature dependency regimes of the process, and examine the composition dependence of the crossover temperature, detected by dielectric spectroscopy. Moreover, the dielectric data was compared in detail with results obtained by specific heat spectroscopy. This comparison provides new insights in the dynamics and dynamic heterogeneity of the PVME/PS blend system. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussels, Belgium DA - 26.08.2018 KW - Polymer blends KW - Dielectric spectroscopy KW - Specific heat spectroscopy PY - 2018 AN - OPUS4-45917 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yildirim, Arda T1 - Molecular dynamics of dipole functionalized triphenylene-based discotics N2 - Since discovery of discotic liquid crystals (DLCs), consisting of a disklike rigid aromatic core and flexible alkyl chains attached to the core, dating back to Chandrasekhar’s work in 1977, they have been extensively investigated to reveal their fundamental properties and potential for applications. The researches on DLCs in last decades showed that DLCs can be considered as promising materials for organic electronic applications since they exhibit one dimensional high charge mobility along the column axis in a columnar mesophase. The mobilies of the rigid aromatic core and the flexible alkyl chains can influence their application properites, e.g. the charge carrier mobility, therefore, it needs to be explored in detailed. In this study, a series of dipole functionalized triphenylene-based discotics, forming a columnar mesophase, were investigated to reveal the influence of the functionalization on phase behavior, molecular dynamics and as well as conductivity. The molecular mobility of the discotics was probed by broadband dielectric spectroscopy (BDS). In addition to conductivity and localized dynamics, glassy dynamics were also observed. The phase behavior of the material was explored by a power-compansated differential scanning calorimetry (DSC). Beside the phase transition temperatures and enthalpies, thermal glass transitions were found for all the materials. Moreover, the glassy dynamics were further investigated by Flash DSC, which is a chip-based calorimetry technique allows fast heating and cooling rates as high as 10000K/s. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussles, Belgium DA - 26.08.2018 KW - Columnar liquid crystals PY - 2018 AN - OPUS4-45918 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina T1 - Dynamics of nanoscopically confined PVME in thin films of an asymmetric miscible PVME/PS blend N2 - In recent years, substantial efforts have been devoted to investigating nanoscopic confinement of polymers, and its effect on glassy dynamics. Broadband Dielectric Spectroscopy (BDS) was used to study the dynamics of ultra-thin films of PVME/PS 50/50 wt% blend, employing a novel nano-structured capacitor sample arrangement. The investigated system shows a complex dynamic behavior. First, an α-relaxation, related to a bulk-like layer was found. Second, an α’-relaxation was observed, characteristic for dynamically asymmetric blends, where the out of equilibrium dynamics is attributed to weakly-cooperative PVME segments relaxing within a frozen environment of PS segments. Third, for thinnest films, an Arrhenius-like process was dominant in the dielectric spectra, indicating localized fluctuations of the segments. Relaxation rates of this process resembled that of the degenerated α-relaxation of the adsorbed layer, found for pure PVME [1], thus it was assigned accordingly. For thinnest films, this process undergoes a further confinement, due to the topological constraints, introduced by PS. Such multiple confinement effect has not been reported for ultra-thin films of polymer blends, before this study [2]. [1] Madkour, S. et al. ACS Appl. Mater. Interfaces 2017, 9, 7535. [2] Madkour, S. et al. ACS Appl. Mater. Interfaces 2017, 9, 37289. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussels, Belgium DA - 26.08.2018 KW - Polymer blends KW - Thin polymer films KW - Dielectric spectroscopy KW - Specific heat spectroscopy PY - 2018 AN - OPUS4-45919 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Investigations on the degree of damage of polyethylene grades as materials of heating oil storage tanks after a service life of more than 30 years N2 - Tanks for heating oil made of polyethylene grades have been on the market since the early 1970s in Germany. Tank manufacturers recommend the replacement of the tanks after a period of 30 years due to guarantee safety. Polyethylene grades are subject to ageing by alteration of the properties during their life cycle. The degree of ageing and the nature of the degradation process mainly depend on the chemical degradation of the polyethylene, the wall thickness of the tank and the environmental conditions. There are no results available on the long-term behavior of the polyethylene grades, especially after a service life of more than 30 years. The aim of this investigation was the determination of the factual degree of damage in comparison to the uncontaminated polyethylene grades. Material data of the used polyethylene grades are available because the BAM was the competent authority for the tests and expert reports for the approval of these tanks until the middle of the 1990s. The determination of the Melt Flow Rate (MFR) and the Fourier Transmission IR Spectroscopy (FTIR) of tank sections from the bottom, the shell and the roof of 10 segregated heating oil storage tanks produced of polyethylene grades A and B were used as tests methods. The MFR measurements of the tank sections showed differences in the values depending on the weight which was used (5 kg or 21.6 kg). A reduction of the MFR values was measured for most of the sections of tanks made of polyethylene grade B after a service life of the tanks of more than 30 years. This grade is mainly subject to the internal ageing by cross-linkages, increased degree of branched molecules and loss of the plasticizer, and to a lesser extent by oxidative degradation. The FTIR analysis, especially of tank sections of the bottom and the shell showed that the intensity of the CH2 asymmetric and symmetric stretching vibrations in the range: 2800 - 2900 cm-1 and the CH2 bending deformation vibration at 1400 cm-1 increased due chain scissions. The intensity of the carbonyl stretching vibration C=O at 1740 cm-1 is low. The carbonyl index characterizes the degree of oxidation. T2 - EUROCORR 2018 CY - Krakow, Poland DA - 09.09.2018 KW - Heating oil storage tanks KW - Polyethylene KW - Degree of damage KW - Melt Flow Rate (MFR) KW - FTIR PY - 2018 AN - OPUS4-45939 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rosemann, Paul A1 - Baumann, O. A1 - Müller, C. T1 - Influence of the post-weld surface treatment on the corrosion resistance of the duplex stainless steel 1.4062 N2 - The duplex stainless steel 1.4062 (X2CrNiN22-2) is used as alternative material to austenitic stainless steels in the construction industry. The corrosion resistance of welded seams is influenced by the base material, the weld filler material, the welding process and also by the final surface treatment. The scale layer next to the weld seam can be removed by grinding, pickling, electro-polishing or blasting depending on the requested corrosion resistance. Blasted surfaces are often used in the industrial practice due to the faster and cheaper manufacturing process compared to pickled or electro-polished surfaces. Furthermore blasting with corundum-grain is more effective than blasting with glass-beads which also lower the process costs. In recent years, stainless steel surfaces showed an unusually high susceptibility to pitting corrosion after grinding with corundum. For this reason, it is now also questioned critically whether the corrosion resistance is influenced by the applied blasting agent. This question was specifically investigated by comparing grinded, pickled, corundum-grain- and glass-bead-blasted welding seams. Results of the SEM analyses of the blasting agents and the blasted surfaces will be presented and correlated with the results of different corrosion tests (KorroPad-testing and pitting potentials). T2 - Materials Science and Engineering 2018 (MSE) CY - Darmstadt, Germany DA - 26.09.2018 KW - Duplexstahl KW - Korrosion KW - Nichtrostender Stahl KW - Schweißen KW - Oberflächenbearbeitung KW - Strahlen KW - KorroPad PY - 2018 AN - OPUS4-46090 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gardei, André T1 - Probenpräparation für LIBS-Messungen - ein häufig unterschätztes Thema N2 - Die Probenpräparation ist ein Teil im Prozess der Baustoffuntersuchung und muss dementsprechend sorgfältig geplant werden. Die Probenpräparation ist letztendlich der Grundstein für alle folgenden Untersuchungen, somit wirken sich alle hier getroffenen Entscheidungen direkt auf die Qualität der Ergebnisse aus. T2 - Fachtagung Bauwerksdiagnose CY - Berlin, Germany DA - 15.02.2018 KW - Probenpräparation KW - LIBS PY - 2018 AN - OPUS4-44656 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from monomers with hydrogen-bonding interactions N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media with applications in the field of drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol. In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and/or 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding. T2 - 7. Jahrestreffen der Seniorexperten Chemie CY - Weimar, Germany DA - 02.05.2018 KW - Thermoresponsive polymer KW - UCST-type polymer KW - Polyacrylamide KW - Water/alcohol mixtures PY - 2018 AN - OPUS4-44845 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lüth, Peter T1 - CEQAT-DGHS Interlaboratory test programme for chemical safety - status and activities N2 - Safety experts, carriers or traders must be able to rely on the validity of the method and on correct results of safety tests and assessments in the laboratory. Bundesanstalt für Materialforschung und –prüfung (BAM), Berlin and Physikalisch-Technischen Bundesanstalt (PTB), Braunschweig have extensive experience in the field of testing and assessment of physical hazards of chemicals. Interlaboratory tests on different test methods have been performed by BAM and PTB during the last 10 years. Significant differences between the results of the participating laboratories were observed in all interlaboratory test. The deviations of the test results were not caused only by laboratory faults but also by deficiencies of the test method; i.e. many of the method descriptions are too ambiguous and allow divergences for interpretation. Therefore, it is necessary to know exactly how good the method is that is used to classify dangerous goods or hazardous substances or to determine safety-relevant parameters. A key criterion is the measurement uncertainty. One can choose simple methods with large error limits, but the measurement uncertainties should be known and always communicated together with the test results. This would allow safety specialists to be able to assess test results correctly and make well-founded decisions, e.g. for adequate protective measures. Interlaboratory tests play a decisive role in assessing the reliability of test results. Participation in interlaboratory tests is not only a crucial element of the quality assurance of laboratories; as such it is explicitly recommended in DIN EN ISO/IEC 17025. In addition, interlaboratory tests are also used to develop and validate test methods and can be used for the determination of the measurement uncertainty. Therefore, the BAM and PTB continue to support the further development of the interlaboratory test programme of CEQAT-DGHS (Centre for quality assurance for testing of dangerous goods and hazardous substances, www.ceqat-dghs.bam.de), established in 2007. This programme is run by BAM in collaboration with the PTB and the QuoData Gesellschaft für Qualitätsmanagement und Statistik mbH, Dresden. A new interlaboratory test for methods validation on the test method UN Test N.5 "Test method for substances which in contact with water emit flammable gases” is currently being prepared and will be carried out in 2018. Laboratories that specialise in this test are invited to participate in the interlaboratory test. Interested laboratories can check the details and register to participate in the interlaboratory test at the CEQAT-DGHS website. T2 - MEETINGS OF IGUS EOS GROUP CY - Shanghai, P. R. China DA - 09.04.2018 KW - Dangerous goods KW - Hazardous substances KW - Test methods validation KW - Quality assurance PY - 2018 AN - OPUS4-44858 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Manolov, Manol T1 - Bestimmung der Maschinennachgiebigkeit beim Einsatz sphärischer Indenter in der Instrumentierten Eindringprüfung N2 - Der Einfluss der Maschinennachgiebigkeit einschließlich der elastischen Verformung des Indenters ist bei der Bestimmung der entsprechenden Werkstoffcharakteristiken insbesondere beim Einsatz von sphärischen Indentern unter höheren Prüfkräften von Bedeutung. Mit zunehmender Prüfkraft wird die Maschinennachgiebigkeit kraftabhängig und kann im idealen Fall als Funktion von Prüfkraft und gemessener Eindringtiefe für vorgegebene Indenterradien dargestellt werden. Angegeben ist ein vereinfachtes Verfahren zur Bestimmung der Maschinennachgiebigkeit. T2 - Sensoren und Messsysteme CY - Nürnberg, Germany DA - 26.06.2018 KW - Maschinennachgiebigkeit KW - Instrumentierte Eindringprüfung KW - Sphärische Indenter KW - Vereinfachtes Verfahren KW - Kraftabhängige Funktion KW - Härtevergleichsplatten KW - Eindringmodul PY - 2018 AN - OPUS4-45390 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -