TY - CONF A1 - Rhode, Michael A1 - Münster, Christoph A1 - Mente, Tobias A1 - Steger, Jörg A1 - Böllinghaus, Thomas T1 - Influence of experimental conditions and calculation method on hydrogen diffusion coefficient evaluation at elevated temperatures N2 - Hydrogen-assisted cracking (HAC) represents a significant failure risk for (high strength) creep resistant low-alloyed steel components in fossil-fired power plant applications at temperatures of up to and above 200 °C. This particularly applies to respective start-up and shut-down processes associated with alternating service-conditions in terms of load flexible power plants. For quantitative determination of localized crack critical hydrogen concentrations, the temperature dependent hydrogen diffusion coefficients have to be determined as exactly as possible. However, available literature provides a wide range of hydrogen diffusion coefficients for low alloyed steels with similar microstructures. Additionally, the available diffusion data seem not to be very reliable and their scatter increases with decreasing temperature. One reason is that the experimental boundary conditions can have a major impact on the determination of respective effective diffusion coefficients. Hence, the scope of this study is to evaluate the influence of the experimental boundary conditions on the derived diffusion coefficients. In addition, different methods for calculating diffusion coefficients are discussed. To elucidate such influences and to draw a line to practical application, the diffusion and trapping behavior in the creep resistant steel 7CrMoVTiB10 10 has been studied. For such purpose, hydrogen charged specimens were isothermally degassed at different temperatures using carrier gas hot extraction (CGHE). Based on experimental data, a numerical model has been developed by which the hydrogen transport behavior and the respective hydrogen distribution during CGHE can be assessed. It is demonstrated that the specimen heating rate has a large influence on the calculated diffusion coefficients under assumption of isothermal degassing which elsewhere has been underestimated in the assessment of diffusion data in creep-resistant steels. The numerical results suggest that calculation methods for diffusion coefficients are limited if compared to experimental results. It also turned out that the sample preparation time before CGHE can enormously influence determined diffusion coefficients. Consequently, non-homogeneous hydrogen concentration profiles have to be anticipated in the simulations to arrive at characteristic effusion curves consistent to respective CGHE experiments. In turn, validated diffusion coefficients are now available for the low-alloyed Cr-Mo-V steel which might be helpful to calculate appropriate hydrogen removal heat treatment procedures, for instance. T2 - International Hydrogen Conference - Material Performance in Hydrogen Environments CY - Jackson Lake Lodge, Moran, Wyoming, USA DA - 11.09.2016 KW - Hydrogen diffusion KW - Elevated temperatures KW - Welding KW - Creep-resistant steel KW - Numerical modeling KW - Calculation PY - 2016 AN - OPUS4-37403 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael A1 - Mente, Tobias A1 - Böllinghaus, Thomas T1 - Modeling of hydrogen-assisted cracking (HAC) in duplex stainless steels (DSS) N2 - Modeling of Hydrogen-Assisted Cracking (HAC) in Duplex Stainless Steels (DSS): - Hydrogen causes significant degradation in DSS and consequently HAC - Mechanisms of HAC have not been fully understood in two-phase microstructures - Mesoscale numerical modeling for HAC in DSS was created, coupled to the macroscale, enabling simulation of HAC in both phases independent from predefined crack paths T2 - International Hydrogen Conference - Material Performance in Hydrogen Environments CY - Jackson Lake Lodge, Moran, Wyoming, USA DA - 11.09.2016 KW - Hydrogen KW - Numerical modeling KW - Duplex stainless steel KW - Hydrogen assisted cracking PY - 2016 AN - OPUS4-37404 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael A1 - Münster, Christoph A1 - Mente, Tobias A1 - Steger, Jörg A1 - Böllinghaus, Thomas T1 - Influence of Experimental Conditions and Calculation Method on Hydrogen Diffusion Coefficient Evaluation at Elevated Temperatures N2 - Hydrogen-assisted cracking (HAC) represents a significant failure risk for (high strength) creep resistant low-alloyed steel components in fossil-fired power plant applications at temperatures of up to and above 200 °C. This particularly applies to respective start-up and shut-down processes associated with alternating service-conditions in terms of load flexible power plants. For quantitative determination of localized crack critical hydrogen concentrations, the temperature dependent hydrogen diffusion coefficients have to be determined as exactly as possible. However, available literature provides a wide range of hydrogen diffusion coefficients for low alloyed steels with similar microstructures. Additionally, the available diffusion data seem not to be very reliable and their scatter increases with decreasing temperature. One reason is that the experimental boundary conditions can have a major impact on the determination of respective effective diffusion coefficients. Hence, the scope of this study is to evaluate the influence of the experimental boundary conditions on the derived diffusion coefficients. In addition, different methods for calculating diffusion coefficients are discussed. To elucidate such influences and to draw a line to practical application, the diffusion and trapping behavior in the creep resistant steel 7CrMoVTiB10 10 has been studied. For such purpose, hydrogen charged specimens were isothermally degassed at different temperatures using carrier gas hot extraction (CGHE). Based on experimental data, a numerical model has been developed by which the hydrogen transport behavior and the respective hydrogen distribution during CGHE can be assessed. It is demonstrated that the specimen heating rate has a large influence on the calculated diffusion coefficients under assumption of isothermal degassing which elsewhere has been underestimated in the assessment of diffusion data in creep-resistant steels. The numerical results suggest that calculation methods for diffusion coefficients are limited if compared to experimental results. It also turned out that the sample preparation time before CGHE can enormously influence determined diffusion coefficients. Consequently, non-homogeneous hydrogen concentration profiles have to be anticipated in the simulations to arrive at characteristic effusion curves consistent to respective CGHE experiments. In turn, validated diffusion coefficients are now available for the low-alloyed Cr-Mo-V steel, which can be helpful to calculate appropriate hydrogen removal heat treatment procedures. T2 - Project Meeting CAStLE CY - Colorado Springs, CO, USA DA - 07.09.2016 KW - Hydrogen KW - Diffusion Coefficient KW - Elevated Temperatures KW - Numerical Modeling KW - Carrier Gas Hot Extraction PY - 2016 AN - OPUS4-37408 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit A1 - Schwarzer, Stefanie A1 - Eiben, Mario T1 - Comparison of the environmental stress cracking behaviour of polyethylene and polyethylene terephthalate as materials for dangerous goods packagings N2 - The chemical industry has expressed great interest in using polyethylene terephthalate (PET) as material for packagings for the transport of dangerous goods. Due to the high strength and stiffness of PET, the wall thickness and weight of packagings can be reduced. This is a relevant cost factor. PET is a semi-crystalline thermoplast which is produced by polycondensation of terephthalic acid and ethylene glycol. According to the European dangerous goods regulations RID and ADR, samples of PET design types of packagings for dangerous goods must be pre-stored with the original filling good for six months at 23°C, before the design type tests can be carried out. For packagings made of polyethylene (PE) tests to prove the stress cracking resistance by using laboratory methods are possible to reduce time and costs. Therefore, standard liquids, simulating the different types of damaging effects on PE are defined in RID and ADR. However, there is no information and research available about the damaging mechanisms on PET in comparison to PE, especially regarding to stress cracking resistance and test methods. The aim of this work is to compare the stress cracking resistance of PE and PET with the Full Notch Creep Test (FNCT), which was developed by chemical industry and is described in the standards EN ISO 16101 and EN 15507. It was investigated whether testing specimens made of PE and PET with a full coplanar notch around the middle of the specimens show weakening after the impact of a tensile force in a wetting solution (Lutensol® FSA 10) at 50°C in a test device on the basis of the FNCT. The test results confirmed the suitability of the method for eight PE grades. Unfortunately, this method couldn’t be used for PET because the specimens broke during notching. In addition the molding of the sheets and the following temper process for twelve hours are very time-consuming, and the specimens broke during notching due to the high brittleness of PET. Another possibility to provide evidence of stress cracking resistance of PE packagings is laid down in BAM’s Dangerous Goods Rule BAM-GGR 015. This test was carried out with PE and PET bottles to compare both materials. Therefore 1l test bottles were filled with a 5% wetting solution and mounted with a clamping tool for 28 days at 40°C. Tensile test specimens were cut out afterwards from the middle of the bottles in the deformed areas. Tensile strength and breaking elongation of PE specimens were determined in comparison to the PET specimens. The tensile properties of the PET specimens couldn’t be determined due to the strength and the stiffness of the material. In conclusion the only way to provide information about the stress cracking resistance of PET was to perform stacking tests. 1l bottles made of PE and PET were filled with a 5% wetting solution and stored with a stacking load for 28 days at 40°C according to EN ISO 16495. Design types of PE and PET both passed the stacking tests. T2 - EUROCORR 2016 CY - Montpellier, France DA - 11.09.2016 KW - polyethylene terephthalate KW - stress cracking resistance KW - test methods KW - dangerous goods packagings PY - 2016 AN - OPUS4-37448 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Holzweber, Markus A1 - Sobol, Oded A1 - Wirth, Thomas A1 - Böllinghaus, Thomas A1 - Unger, Wolfgang T1 - Deuterium permeation and cracking in duplex steels as viewed by ToF-SIMS and HR-SEM with data fusion N2 - Better understanding of hydrogen assisted degradation and trapping mecha-nisms requires sufficient imaging techniques for respective hydrogen-microstructure interaction studies, in particular with multi-phase metallic micro-structures [1]. The present work is focusing on the elucidation of deuterium be-havior in two austenitic-ferritic duplex stainless steels (DSS) under the assumption that deuterium behaves in many ways similarly to hydrogen [2]. For case studies standard 2205 and lean 2101 DSSs were chosen due to the extensive use of these steels in industry [3]. The analyses were conducted by using a novel in-situ permeation and Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) imaging technique or by ex-situ ToF-SIMS imaging following electrochemical charging experiments. Another pioneering procedure was data fusion (including chemometry) of results of powerful laterally resolved chemical analysis and high resolution structural characterization techniques . Results for the ex-situ observations showed a different influence of deuterium loading on the two steel grades as well as different damage mechanisms in each phase. Formation of sub-surface blisters between the ferrite and austenite were obtained in both the standard and the lean DSS. In both steels, an increased deuterium concentration was observed around deformed regions such as cracks, confirming that they originate from the presence of deuterium [4]. The formation of parallel cracks was obtained only in the austenite within the standard duplex whereas in the lean duplex the highest intensity of deuterium was obtained in the austenite along the ferrite-austenite interphase. In comparison, application of the novel in-situ permeation technique enabled to register and record the deuterium permeation through the material and the respective saturation sequence of the two phases as well as the interfaces. Faster diffusion of the deuterium was observed in the ferrite and a direct proof for deuterium enrichment at the austenite-ferrite interface has been given [1]. The integration of the specified techniques gives a better insight into the processes leading to hydrogen induced failure. These two experimental techniques provide very valuable tools for elucidation of respective metallurgical failure mechanisms that can be used for the validation of respective numerical models for hydrogen assisted cracking (HAC). T2 - 19. Arbeitstagung Angewandte Oberflächenanalytik CY - Soest, Germany DA - 05.09.2016 KW - ToF-SIMS KW - Hydrogen assisted cracking KW - Data fusion KW - SEM PY - 2016 AN - OPUS4-37484 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheuerlein, A1 - Lackner, F. A1 - Savary, F. A1 - Rehmer, Birgit A1 - Finn, Monika A1 - Uhlemann, P. T1 - Mechanical properties of the HL-LHC 11 Tesla Nb3Sn magnet constituent materials N2 - A test campaign was launched to determine the mechanical properties of the HL-LHC 11 T Nb3Sn magnet components in order to accurately model the mechanical properties in Finite Element simulations that predict the stress and strain distribution in These magnets. Static and dynamic test methods have been applied for determining elastic materials behavior, and highly accurate Young’s moduli are obtained with the dynamic methods resonance and impulse excitation. These non-destructive methods also enable temperature dependent modulus measurements during in situ heat cycles. T2 - Applied Superconductivity Conference CY - Denver, Colorado, USA DA - 04.09.2016 KW - Young's modulus KW - Tensile test KW - Resonanz KW - Impact excitation PY - 2016 AN - OPUS4-37414 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin A1 - Burkert, Andreas A1 - Heyn, A. T1 - Corrosion investigations by using gel-type electrolytes N2 - In the presentation different zinc coatings are presented and investigated. Their naturally formed protective layers are electrochemically characterized and corrosion relevant values are determined by using a gel pad based on polysaccharide. The corrosion relevant values allow the differentiation of various zinc coating systems and can describe the current protective effect provided by the coating. It is shown that gel-type electrolytes influence protective layers and coatings considerably less than corresponding bulk electrolytes. From the results it is evident that gel-type electrolytes represent a viable and promising field in corrosion research.zeige mehr T2 - EUROCORR European Corrosion Congress 2016 CY - Montpellier, France DA - 11.09.216 KW - Corrosion investigations KW - Gel-type electrolytes KW - Zinc coatings PY - 2016 AN - OPUS4-37496 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lüth, Peter A1 - Brandes, E. A1 - Frost, K. A1 - Kurth, Lutz A1 - Schmidt, Martin A1 - Michael-Schulz, Heike A1 - Uhlig, S. T1 - CEQAT-DGHS Ringversuchsprogramm der BAM in Kooperation mit QuoData und PTB N2 - Bei der Bewertung der Verlässlichkeit der im Labor gewonnenen Prüfergebnisse spielen Ringversuche eine entscheidende Rolle. Die Bundesanstalt für Materialforschung und -prüfung (BAM) unterstützt deshalb den weiteren Ausbau des Ringversuchsprogramms des im Jahr 2007 gegründeten Kompetenzzentrums zur Qualitätssicherung für Prüfungen von Gefahrgütern und Gefahrstoffen auf physikalische Gefahren (Centre for quality assurance for testing of dangerous goods and hazardous substances, CEQAT-DGHS). Bei allen bisher untersuchten Prüfmethoden besteht ein Verbesserungsbedarf. Die RV müssen daher zunächst auf die Methodenentwicklung, -verbesserung und -validierung abzielen und nicht auf Leistungstests. T2 - 14. Kolloquium zur chemischen und physikalischen Sicherheitstechnik (BAM-PTB-Kolloquium) CY - Berlin, Germany DA - 14.06.2016 KW - Gefahrgut KW - Gefahrstoff KW - Ringversuch KW - Prüfmethode KW - Validierung KW - Qualitätssicherung PY - 2016 AN - OPUS4-38465 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jürgens, Maria A1 - Olbricht, Jürgen A1 - Skrotzki, Birgit A1 - Fedelich, Bernard T1 - Ermüdungsverhalten, Lebensdauer und Schädigungsprozesse von P92 unter zyklischen Betriebsbedingungen N2 - Schnelle Lastwechsel mit hohen Temperaturgradienten führen zu thermischen und mechanischen Beanspruchungen v.a. in dickwandigen Bauteilen. Daraus ergibt sich ein komplexes Lastkollektiv, bei dem der Werkstoff sowohl durch Kriechermüdung als auch durch thermomechanische Ermüdung (TMF) geschädigt wird. Welche Auswirkungen hat eine gleichzeitige Änderung von Temperatur, mechanischer Beanspruchung und Arbeitsmedium auf die Schädigungsprozesse? T2 - KWT Dresden CY - Dresden, Germany DA - 18.10.2016 KW - LCF KW - P92 KW - TMF PY - 2016 AN - OPUS4-38587 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hemmleb, M. A1 - Bettge, Dirk A1 - Berger, D. A1 - Driehorst, I. T1 - 3D surface reconstruction with segmented BSE detector: New improvements and application for fracture analysis in SEM N2 - Application of 4Q-BSE detector and dedicated software enables 3D surface measurements of fracture samples in SEM. 3D surface measurement is independent from magnification and material invariant. Quantitative height measurements require careful detector adjustment and system calibration. Live 3D view allows a fast assessment of topographical features. In addition to SE and BSE imaging, 3D surface data help to analyse and interpret fracture samples. T2 - European Microscopy Congress 2016 CY - Lyon, France DA - 28.08.2016 KW - Topography KW - SEM KW - 3D analysis KW - Fractography PY - 2016 AN - OPUS4-38456 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sojref, Regine A1 - Nofz, Marianne A1 - Dörfel, Ilona A1 - Schulz, Wencke A1 - Wollschläger, Nicole A1 - Kranzmann, Axel T1 - Thin and porous sol-gel alumina coatings on a 9% Cr steel as a protection against high-temperature corrosion in power plants N2 - In order to reduce CO2 emissions fossil fuelled power stations with high combustion efficiency are being developed. The increase of the operating temperature, a common way to improve combustion efficiency, leads to enhanced corrosion of heat exchange steel tubes in the power plants. Within the framework of the European project “Production of Coatings for New Efficient and Clean Coal Power Plant Materials” (POEMA)", high temperature corrosion protection coatings are now under investigation. Thin porous sol-gel alumina films are promising candidate coating materials. Coatings were prepared by applying boehmite sols on grinded steel P92 and subsequent heat treatments at temperatures up to 650 °C. Thus a porous layer of worm-like particles was formed consisting of nano-crystallites and amorphous alumina. A dense interface with satisfying adhesion resulted from diffusion of chromium and iron ions out of the steel into the porous coating. However, the film locally exhibited some cracks caused by steep edges in the grinded steel surface. An appropriate substrate pretreatment should avoid this problem. The protection of the steel relies on the barrier function of the alumina coating and the formation of a dense chromia layer at the steel surface. T2 - ICC6 6th International Congress on Ceramics CY - Dresden, Germany DA - 21.08.2016 KW - High-temperature corrosion KW - Alumina KW - Chromium PY - 2016 AN - OPUS4-38354 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shashev, Yury A1 - Kupsch, Andreas A1 - Lange, A. A1 - Bruno, Giovanni A1 - Müller, Bernd R. A1 - Hentschel, M.P. A1 - Britzke, Ralf T1 - Optimizing visibility of phase gratings for Talbot-Lau X-ray imaging N2 - We investigated the efficiency of phase gratings, i.e., the visibility upon variation of different parameters. Rotating around an axis parallel to the grid lines of the phase grating changes the grating’s shape and thereby the initial distribution of phase shifts. This yields high visibilities for shorter propagation distances than derived from box shapes. Tilting the grating in the scattering plane allows continuous tuning of the grating’s height that corresponds to an ideal phase shift for a particular photon energy. This opens the way for tuning the design energy suitable for the material under investigation. Our study included simulations for monochromatic sources with the sampling procedure for rectangular and triangular phase gratings. T2 - HZB - 8th joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 07.12.16 KW - Phase grating KW - X-ray interferometry KW - X-ray imaging PY - 2016 AN - OPUS4-38823 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Ben T1 - Aging of composite pressure cylinder (COD-AGE) N2 - Subject, Aim and methods within the Project COD-AGE. Test methods and condition monitoring for Composite-cylinders T2 - Follow-up Workshop on statistical safety assessment CY - Berlin, Germany DA - 05.10.2016 KW - Aging KW - Composite cylinder KW - Non destructive testing PY - 2016 AN - OPUS4-39087 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Ben A1 - Munzke, Dorit A1 - Schukar, Marcus T1 - Zustandsüberwachung von Composite-Druckgefäßen mit faseroptischer Sensorik N2 - Einsatz der Faseroptik zur Zustandsüberwachung von Composite-Druckgefäßen. Aufbau, Integration, Messergebnisse. T2 - Follow-up Workshop on Statistical Safety Assessment of Composite Cylinders CY - Berlin, Germany DA - 05.10.2016 KW - Faseroptik KW - Zustandsüberwachung KW - Composite-Druckgefäße PY - 2016 AN - OPUS4-39088 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Laquai, René A1 - Müller, Bernd R. A1 - Kupsch, Andreas A1 - Nellesen, J. A1 - Tillmann, W. T1 - Characterizing damage evolution in metal matrix composites with X-ray refraction topography and in situ tensile loading N2 - In this study a metal-matrix-composite with aluminum matrix and Al2O3 particles was investigated with x-ray refraction topography and in-situ tensile loading. It could be observed that after reaching a certain load the specific surface increased steadily. However, the classical radiographs taken for comparison show no damage in the sample. T2 - 8th Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 07.12.2016 KW - X-ray refraction KW - Metal matrix composites KW - In-situ loading KW - Synchrotron PY - 2016 AN - OPUS4-39113 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas A1 - Lange, Axel A1 - Bruno, Giovanni A1 - Müller, Bernd R. A1 - Hentschel, Manfred A1 - Britzke, Ralf T1 - Optimizing visibility of phase gratings for Talbot-Lau X-ray imaging N2 - We investigated the efficiency of phase gratings, i.e., the visibility upon variation of different parameters. Rotating around an axis parallel to the grid lines of the phase grating changes the grating’s shape and thereby the initial distribution of phase shifts. This yields high visibilities for shorter propagation distances than derived from box shapes. Tilting the grating in the scattering plane allows continuous tuning of the grating’s height that corresponds to an ideal phase shift for a particular photon energy. This opens the way for tuning the design energy suitable for the material under investigation. Our study included simulations for monochromatic sources with the sampling procedure for rectangular and triangular phase gratings. T2 - User-Meeting CY - Berlin, Germany DA - 8.12.2016 KW - Talbot-Lau interferomerty KW - Phase grating KW - Synchrotron radiation PY - 2016 AN - OPUS4-39096 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Munzke, Dorit A1 - Becker, Ben A1 - Schukar, Macus T1 - Zustandsüberwachung von Composite-Druckgefäßen mit faseroptischer Sensorik N2 - Funktionsweise, Integration und Messergebnisse von opt. Fasern zur Zustandsüberwachung von Composite-Druckgefäßen. T2 - 3. Workshop Themenfeld Material CY - Berlin, Germany DA - 12.10.2016 KW - Faseroptik KW - Zustandsüberwachung KW - Composite-Druckgefäße PY - 2016 AN - OPUS4-39097 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Armatys, Kamila A1 - Adamczyk, Burkart A1 - Adam, Christian A1 - Galetz, M.C. A1 - Pflumm, R. T1 - Corrosion and abrasion resistant protective coatings for biomass combustion N2 - One of the alternative renewable fuels is biomass but it is a difficult fuel because of its diversity and complexity. It can contain high percentages of K and Cl responsible for corrosion together with sand that have additionally an abrasive effect during combustion. Because of permanently extending the surface reaction due to abrasion the corrosion of the materials increases. In particular in power plants, the superheater tubes are exposed to a corrosive abrasive attack that is one of the main sources of concern. The development of new alloys for multilayer surface, which combines corrosive and abrasive resistance is therefore of high importance. Those new technical approaches must be at the same time cost-effective to be an alternative to conventional materials. The aim of the presented investigation methods is to test and develop suitable alloys for coatings for the super heater tubes of biomass power plants. First results of abrasion investigations show improved abrasion resistance compared to the multi-component reference material Alloy 625. T2 - Young Researchers Conference: Energy Efficiency & Biomass CY - Wels, Austria DA - 24.02.2016 KW - Coatings KW - Corrosion PY - 2016 AN - OPUS4-35713 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Harald Rune A1 - Hoffmann, Katrin A1 - Schwibbert, Karin A1 - Sameith, Janin A1 - Toepel, Jörg A1 - Resch-Genger, Ute T1 - Imaging of local pH in biofilm using polymeric sensors: towards the elucidation of microbial induced corrosion N2 - Microbial induced corrosion (MIC) is a crucial problem in many technical plants as well as fuel tanks, leading to considerable damage and huge financial losses. Successful prevention of MIC requires the localization of first signs of corrosion as well as the identification of factors influencing the corrosion process. In this respect, also the determination of corrosion rates can be of interest for the possible prevention of MIC. Hence, there is a growing need for sensitive and preferably inexpensive tools that enable the early detection of MIC. Of special interest are methods, which provide spatially and time-resolved information and allow the study of changes on metal surfaces as prerequisites for a more detailed analysis of ongoing corrosion processes at a MIC-affected site. Biofilm formation can lead to changes in pH, oxygen and chloride concentration as well as to the release of certain metal ions like Fe(II) and Mn(II) depending on the type of metal surface involved. Hence, optical methods enabling the detection of these analytes at very low concentration and monitoring of their changes can be used for MIC detection. Here, we propose to utilize polymeric nanosensors for MIC detection via the determination of the local pH value changes in different biofilms. Such nanosensors are known to have several advantages in imaging applications such as intracellular pH measurements including the ease of doping or labeling with a multitude of analyte-responsive and inert dye molecules for the realization of a high analyte sensitivity and ratiometric sensing. Moreover, they can be surface functionalized with target-specific ligands e.g., lectins, for the specific binding to the outer surface of certain types of bacteria. In this respect, different polymer architectures will be studied to identify an optimal candidate in terms of imaging performance in conjunction with several classes of pH-responsive fluorescent dyes like cyanines, aza-BODIPYs, and xanthenes, utilizing different mechanism of signal generation such as photo-induced electron transfer or protonation-induced changes in the spectral position of absorption and emission spectra. T2 - Europtrode CY - Graz, Austria DA - 20.03.2016 KW - Nanosensor KW - Microbial induced corrosion KW - Imaging KW - Nanosensor KW - Mikrobiell induzierte Korrosion KW - Bildgebung PY - 2016 AN - OPUS4-35628 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Steinborn, Gabriele A1 - Woydt, Mathias A1 - Gemeinert, Marion T1 - Stable aqeous niobium carbide suspensions for production of homogeneous hard materials N2 - Hard materials consist of a hard phase embedded in a metallic binder. In order to achieve high toughness and strength, it is necessary to have a perfect mixing of hard phase and binder, which is mainly achieved by ball milling. Niobium carbide (NbC) has a high potential to substitute tungsten carbide as hard material. The publication presents the development of stable homogeneous and de-agglomerated NbC-dispersions. To prevent agglomeration of the powder, stable suspensions were achieved by surface treatments with the dispersants (PD and HD), which resulted in a charge reversal from a negative to a positive zeta potential. This surface-modified powder guaranteed a stable re-dispersion in the binder suspension. Nickel powder was added as metallic binder. This suspension was suited for 3D-printing. The green samples could be sintered in vacuum or Argon atmosphere. T2 - 91. Jahrestagung der deutschen keramischen Gesellschaft CY - Freiberg, Germany DA - 07.03.2016 KW - Niobium carbide powder KW - Stable suspensions KW - Reduction of agglomerates PY - 2016 AN - OPUS4-35636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Taabache, Soraya A1 - Bertin, Annabelle A1 - Maskos, M. T1 - Microfluidic-Assisted Self-Assembly of Dendritic Amphiphiles N2 - The controlled production of supramolecular aggregates formed by the self-assembly of dendritic amphiphiles is of great interest owing to their potential application in the fields of nanotechnology and nanomedicine. Dendritic amphiphiles as building blocks offer the advantage that their structure and size can be precisely tuned through organic synthesis. This synthetic flexibility enables the fine-tuning of the hydrophobic to hydrophilic ratio of the dendritic segments, which mainly controls the morphology of the self-assembled structures. A promising method for the controlled preparation of supramolecular assemblies is based on the use of micromixers.[5,6] Due to their mixing times in the range of milliseconds at the microscale level, the application of such microfluidic systems benefits from a high mixing efficiency, a low mixing time and a reproducible synthesis compared to conventional batch-based techniques such as the solvent injection method or the film hydration method. Herein, we report on the microfluidic-assisted self-assembly of several dendritic amphiphiles and the impact of the mixing parameters on the self-assembly process. T2 - Makromolekulares Kolloquium 2016 CY - Freiburg im Breisgau, Germany DA - 24.02.2016 KW - Dendritic amphiphiles KW - Self-assembly KW - Dendrimersomes KW - Micromixer KW - Microfluidic PY - 2016 AN - OPUS4-35477 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Oesch, Tyler T1 - In-situ CT investigation of pull-out failure for reinforcing bars embedded in conventional and high-performance concretes N2 - The use of high-performance concretes holds great promise for many structural applications. This paper investigates the performance of these materials when used in combination with traditional reinforcing bars. An improved understanding of failure during reinforcing bar pull-out from high-performance concretes is needed in order to better predict the embedment length required to develop full reinforcing bar pull-out strength and the required thickness of reinforcing bar cover for adequate corrosion protection. The cracking structures surrounding the reinforcing bars were analyzed using x-ray computed tomography (CT) in order to determine the stress states causing failure. This was accomplished by conducting in-situ reinforcing bar pull-out experiments during CT scanning. A conventional concrete, a high-strength concrete, and a high-strength fiber reinforced concrete were all tested during the experiments. The results of these experiments showed that the levels of brittleness of the different concrete materials had a major impact on the failure mechanisms that they experienced during reinforcing bar pull-out. It was also clear that the specimen geometry and the casting method had a major impact on fiber orientation. The inclusion of fibers within concrete was also found to significantly improve strength and corrosion protection during reinforcing bar pull-out. T2 - 6th Conference on Industrial Computed Tomography CY - Wels, Austria DA - 09.02.2016 KW - Fiber KW - Reinforcing Bar KW - Computed Tomography KW - In-Situ KW - High-Performance Concrete PY - 2016 AN - OPUS4-35521 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lauer, Franziska A1 - Kneipp, Janina A1 - Weidner, Steffen A1 - Seifert, Stephan T1 - Multivariate statistics applied to MALDI-TOF MS data of pollen samples N2 - Current pollen screening information networks are based on time-consuming, microscopic determination of the genus-specific pollen morphology. Additionally, the given information relies on prediction of plant growth, wind direction and seasonal information. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was introduced for rapid analysis of complex biological samples. MALDI-TOF provides the possibility to measure species-specific mass peak patterns of pollen and offers a powerful tool for investigation of taxonomic relations. Our objective is to develop a fast, reliable, routine method for detecting single pollen grains in pollen mixtures. The obtained spectra are analyzed by multivariate statistics. T2 - 49. Jahrestagung der Deutschen Gesellschaft für Massenspektrometrie CY - Hamburg DA - 28.02.2016 KW - Pollen KW - Datenanalyse KW - Hauptkomponentenanalyse PY - 2016 AN - OPUS4-35523 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fischer, Franziska A1 - Joester, Maike A1 - Rademann, K. A1 - Emmerling, Franziska T1 - Survival of the fittest - Competetive cocrystal reactions in the ball mill N2 - Mechanochemistry is increasingly used for synthesizing various materials including cocrystals and metal organic compounds. Although this synthesis approach offers a fast and pure synthesis in high yields there is a lack in understanding the mechanisms of milling reactions. The driving forces triggering the formation of cocrystals under milling conditions were investigated using a set of multi-component competitive milling reactions. In these reactions, different active pharmaceutical ingredients were ground together with a further compound acting as coformer. The study was based on new cocrystals including the coformer anthranilic acid. The results of the competitive milling reactions indicate that the formation of cocrystals driven by intermolecular recognition are influenced and inhibited by kinetic aspects including the formation of intermediates and the stability of the reactants. T2 - Berliner Chemie Symposium CY - Berlin, Germany DA - 12.04.2016 KW - milling KW - cocrystal KW - mechanochemistry PY - 2016 AN - OPUS4-35862 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Greiser, Sebastian A1 - Sturm, Patrick A1 - Gluth, Gregor A1 - Hunger, M. A1 - Jäger, Christian T1 - 29Si-27Al NMR to verify and distinguish Qn(mAl) sites in zeolites and geopolymers N2 - One-part-geopolymers, produced by addition of water to a mixture of solid silica and sodium alumi-nate, are a less exhaustively studied approach to form geopolymeric binders. Depending on the silica source, the reaction products show significant amounts of zeolite Na-A besides amorphous compounds. Previously, 29Si MAS NMR has been used to analyze the chemical structure of such one-part geopolymers, having crystalline structures and amorphous phases (Q2, Q3, Q4). In this work, pure zeolites and three different one-part-geopolymers cured for 1 day were investigated by 29Si-27Al TRAPDOR NMR. It was used to identify aluminum phases in overlapping silicon sites. Zeolites Na-X (Si/Al=1.4) and Na-Y (Si/Al=2.7) served as model systems to measure the TRAPDOR effect of the structural units Q4(mAl). Both materials show several Q4(mAl) signals, which are all separated by their chemical shifts. The more aluminum surrounds the silicon tetrahedron the higher are the normalized TRAPDOR difference signals (S0/∆S). The intensity ratios between Q4(mAl) to Q4({m-1}Al) of these signals is fixed but vary slightly between both zeolites. These results are transferred to the complex geopolymer structure. T2 - 57th Experimental nuclear magnetic resonance conference CY - Pittsburgh, PA, USA DA - 10.04.2016 KW - NMR KW - 29Si-27Al TRAPDOR MAS KW - Geopolymer KW - One-part formulation KW - Rice husk ash PY - 2016 AN - OPUS4-35864 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nguyen, Thi Yen A1 - Bernardes, C. A1 - Minas da Piedade, M. E. A1 - Rademann, K. A1 - Emmerling, Franziska T1 - Direct evidence of polyamorphism in paracetamol N2 - While polymorphism is a common phenomenon in the crystallization processes of organic compounds, polyamorphism has gained importance only recently. Using sophisticated sample environments and applying in situ scattering methods and vibrational spectroscopy, the complete crystallization process of organic compounds from solution can be traced and characterized. Diffuse scattering from amorphous intermediates can be investigated by analyzing the atomic pair Distribution function (PDF) to gain further insights into molecular pre-orientation. The crystallization behavior of Paracetamol was studied exemplarily under defined, surface-free conditions. Based on the choice of the solvent, the formation of different polymorphs is promoted. The thermodynamically stable form I and the metastable orthorhombic form II could be isolated in pure form directly from solution. For both polymorphs, the crystallization from solution proceeds via a distinct amorphous precursor phase. PDF analyses of these different amorphous states indicate a specific pre-orientation of the analyte molecules introduced by the solvent. The resulting crystalline polymorph is already imprinted in these proto-crystalline precursors. Direct experimental evidence for the polyamorphism of paracetamol is provided. T2 - Annual CM1402 crystallize COST meeting CY - Coimbra, Portugal DA - 06.04.2016 KW - Paracetamol KW - Crystallization KW - In situ analysis KW - Active pharmaceutical ingredient (API) PY - 2016 AN - OPUS4-35873 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wallau, Wilma A1 - Pirskawetz, Stephan A1 - Meng, Birgit T1 - Alkali-Kieselsäure-Reaktion in Beton - Entwicklung eines Prognoseverfahrens N2 - Zur Vermeidung der schädigenden Alkali-Kieselsäure-Reaktion in Betonbauwerken wird die Alkalireaktivität von Gesteinskörnungen im Vorhinein getestet. Der 60°C-Betonversuch ermöglicht eine vergleichsweise schnelle Einschätzung nach fünf-monatiger Testzeit. Dazu wird die Dehnung von Betonprüfkörpern, die mit der zu testenden Gesteinskörnung hergestellt wurden, manuell alle 28 Tage gemessen. Ein alternatives, an der BAM in den vergangen Jahren entwickeltes Verfahren setzt Dehnungssensoren ein, um kontinuierlich und online zu messen. Die Dehnungskurven sind eine gute Grundlage sowohl für die Prognose vom Expansionsverhalten während des Tests als auch für die Validierung von Expansionsmodellen. T2 - 3. Workshop im Themenfeld Material zu den Schwerpunktthemen "Laufende Projekte und neue Aktivitäten" CY - Berlin, Germany DA - 12.10.2016 KW - Baustoffe KW - Alkali-Kieselsäure-Reaktion PY - 2016 AN - OPUS4-40156 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rosemann, Paul A1 - Baumann, O. A1 - Müller, C. A1 - Gottwald, W.-R. A1 - Modersohn, W. T1 - Einfluss der Oberflächennachbearbeitung auf die Korrosionsbeständigkeit von Schweiß-nähten des Duplexstahls 1.4062 N2 - Die Korrosionsbeständigkeit geschweißter Konstruktionen aus nichtrostenden Duplexstählen wird von den Schweißparametern und der Nachbehandlung der Oberflächen bestimmt. Eine etablierte Methode der Schweißnahtnachbehandlung ist das Strahlen der Oberfläche mit Glasperlen. Diese Methode soll aus wirtschaftlichen Gründen durch das Strahlen mit Korund ersetzt werden, welches deutliche Zeit- und Kostenvorteile bietet. Besonders bei der Lochkorrosionsbeständigkeit hat sich das Schleifen mit Korund bereits als nachteilig erwiesen, weshalb diese Umstellung auch beim Stahlen kritisch hinterfragt wird. Daher wurden Probeschweißungen bei der Firma Modersohn hergestellt und mit verschiedenen Oberflächenbearbeitungsmethoden (Glasperlenstrahlen, Korundstrahlen, Beizen, Elektropolieren, Schleifen) nachbehandelt. Diese verschiedenen Oberflächenzustände wurden analytisch (REM, Rauheit) charakterisiert und hinsichtlich ihrer Lochkorrosionsbeständigkeit vergleichend untersucht werden, um die Eignung des Strahlens mit Korund zu beurteilen. T2 - GfKORR-Jahrestagung 'Duplex-Stähle – Nische oder Zukunft ?' CY - Frankfurt/M., Germany DA - 15.11.2016 KW - Korrosionsbeständigkeit KW - Schweißnähte KW - Duplexstahl PY - 2016 AN - OPUS4-39470 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rosemann, Paul A1 - Kauss, Norman A1 - Heyn, A. T1 - Einfluss des Schwefelgehalts auf die Korrosionsbeständigkeit des nichtrostenden Stahls 1.4404 N2 - Die Korrosionsbeständigkeit nichtrostender Stähle wird maßgeblich von ihrer chemischen Zusammensetzung bestimmt. Der tendenzielle Einfluss ist für die Hauptlegierungselemente in der wissenschaftlichen Fachliteratur beschrieben. Bei Begleitelement Schwefel gibt es dagegen keine konkreten Untersuchungen die belegen, ab welchem Gehalt mit einer Verringerung der Korrosionsbeständigkeit zu rechnen ist. Im Lichtbogenschmelzofen wurden verschiedene Legierungen mit abgestuftem Schwefelgehalten hergestellt, um den Einfluss dieses Begleitelementes auf die Korrosionsbeständigkeit systematisch zu untersuchen. Die KorroPad-Prüfung und die Bestimmung kritischer Lochkorrosionspotentiale wurden zur Charakterisierung der Legierungen genutzt. Beide Methoden belegen eine zunehmende Verringerung der Lochkorrosionsbeständigkeit mit dem Schwefelgehalt. T2 - GfKORR-Jahrestagung 'Duplex-Stähle – Nische oder Zukunft ? CY - Frankfurt/M., Germany DA - 15.11.2016 KW - Schwefelgehalt KW - Korrosionsbeständigkeit KW - Nichtrostender Stahl PY - 2016 AN - OPUS4-39472 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, C. A1 - Rosemann, Paul A1 - Diehl, V. A1 - Halle, T. T1 - Einfluss der Abkühlgeschwindigkeit auf die Korrosionsbeständigkeit martensitischer nichtrostender Stähle N2 - Martensitische nichtrostende Stähle werden in verschiedenen technischen Bereichen eingesetzt, bei denen eine optimale Kombination aus hoher mechanischer Festigkeit und guter korrosiver Beständigkeit gefordert wird. Beide Eigenschaften werden in der Industrie primär durch die Wärmebehandlung gesteuert. Die Korrosionseigenschaften sind dabei stark von der diffusionsbedingten Bildung und Auflösung von Chromkarbiden abhängig. In vergangenen wissenschaftlichen Arbeiten konnte nachgewiesen werden, dass die Abkühlgeschwindigkeit nach dem Austenitisieren einen großen Einfluss auf die Bildung solcher Karbide hat. Der Einfluss der Abkühlgeschwindigkeit auf die Lochkorrosionsbeständigkeit wurde an den Stählen 1.4108 und 1.4116 systematisch untersucht. Mit Hilfe des Stirnabschreckversuches wurde dabei die Abkühlgeschwindigkeiten variiert und anschließend die Veränderung von Gefüge, Lochkorrosionsbeständigkeit und Härte untersucht. Als Ergebnis konnten kritische Abkühlgeschwindigkeiten ermittelt werden, bei denen eine kritische Verringerung der Korrosionsbeständigkeit einsetzt. T2 - GfKORR-Jahrestagung 'Duplex-Stähle – Nische oder Zukunft ?' CY - Frankfurt/M., Germany DA - 15.11.2016 KW - Korrosionsbeständigkeit KW - Martensitische nichtrostende Stähle KW - Abkühlgeschwindigkeit PY - 2016 AN - OPUS4-39473 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kabelitz, Anke A1 - Dinh, Hoang An A1 - Emmerling, Franziska T1 - Time resolved WAXS studies on the crystallization of Al13 keggin clusters N2 - We report on the in situ investigation of the Al13 sulfate synthesis by WAXS. Al13 sulfates were crystallized by precipitating hydrolyzed aluminum solutions by the addition of sodium sulfate. The measurements were performed using an acoustic levitator. The study provides information about the intermediates during the crystallization process. T2 - Eighth Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 07.12.2016 KW - In situ KW - Crystallization KW - WAXS PY - 2016 AN - OPUS4-39365 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Léonard, Fabien A1 - Tammas-Williams, S. A1 - Todd, I. T1 - CT for additive manufacturing process characterisation: assessment of melt strategies on defect population N2 - Selective Electron Beam Melting (SEBM) is a promising powder bed Additive Manufacturing (AM) technique for near net-shape manufacturing of high-value titanium components. However, as with every emerging technique, the manufacturing processes can still be greatly improved and optimised. In particular, the links between AM settings and the resulting sample porosity is of great interest, as the fatigue life of SEBM parts is currently dominated by the presence of porosity. In this study, the size, volume fraction, and spatial distribution of the pores in model samples have been characterised in 3D, using X-ray Computed Tomography (CT), and correlated to the SEBM process variables. A strong relationship was found with the different beam strategies used to contour, and infill by hatching, a part section. The majority of pores were found to be small spherical gas pores, concentrated in the infill hatched region. Rarer irregular shaped pores were mostly located in the contour region and have been attributed to a lack of fusion between powder particles. T2 - Conference on Industrial Computed Tomography iCT2016 CY - Wels, Austria DA - 09.02.2016 KW - Titanium KW - Additive Manufacture KW - Selective Electron Beam Melting KW - Pores KW - Defects KW - X-ray Computed Tomography PY - 2016 AN - OPUS4-39186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hertwig, Andreas A1 - Rosu, Dana-Maria A1 - Ortel, Erik A1 - Hodoroaba, Vasile-Dan A1 - Krähnert, R. T1 - Measurement of porous TiO2 layers with spectroscopic ellipsometry - a multi-method study N2 - By means of an effective medium (EMA) based approach, it is possible to use spectroscopic ellipsometry to determine the mixing ratios between air and material in porous dielectrics and calculate a quantitative value of the porosity for these materials. As this method is model-based, it is very difficult to provide a quantitative measure for the accuracy of porosity values determined by this method. Valuable additional information can often be obtained by combining ellipsometry with other complementary methods. In the present study, the ellipsometry results were validated by Electron Probe Microanalysis (EPMA) with the option of layer analysis (by the socalled “STRATAGem” approach), gravimetry, and electron microscopy. We analysed porous TiO2 thin layers synthesised by means of a template synthesis Approach (evaporation induced self assembly). Ellipsometry measurements on porous samples are difficult to analyse due to the complexity of the models necessary. Often it is difficult to decide if the measured data contains enough information to successfully determine the target quantities (mixing ratio, dielectric function of the matrix material). One method to decrease the complexity of the fit and therefore use the measurement data most efficiently is a multi-sample analysis. In the present case, multi-sample analysis was used for determining the porosity factors of the individual layers while using one common set of dielectric function values for the matrix in all cases. While the results of the fit analysis in this case can be used to show the feasibility and also the limitations of the multi-method approach, the porosity values themselves show a promising agreement between the Independent methods. It can therefore be concluded that determining porosity values with ellipsometry is in accordance to other methods to the level of accuracy provided by the complementary methodologies. T2 - ICSE-7, 7th International Conference on Spectroscopic Ellipsometry CY - Berlin, Germany DA - 5.6.2016 KW - Spectroscopic ellipsometry KW - Electrolysis KW - Catalysis KW - Thin film metrology KW - Porous materials PY - 2016 AN - OPUS4-39940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rizzo, F. A1 - Agudo Jácome, Leonardo A1 - Mosquera Feijoo, Maria A1 - Nolze, Gert A1 - Kranzmann, Axel A1 - Costa e Silva, A. T1 - Evaluation of nano-sized internal oxidation in a Fe-13Cr alloy exposed to water vapor atmosphere N2 - The topotactic formation of nano-sized precipitates immediately under the internal oxide layer in a Fe-13Cr alloy exposed to oxidizing water vapor atmosphere was recently reported. The precipitates were identified as lath-shaped Fe-Cr spinel exhibiting a crystallographic orientation relationship with the ferritic matrix. The authors proposed that these precipitates could act as a precursor to the formation of the spinel layer observed in the adjacent part of the oxide scale.The occurrence of internal oxidation in Fe–Cr alloys subjected to similar conditions had been previously identified and directly correlated to the presence of water vapor. In the present work, we attempt to rationalize the processes occurring during the oxidation of this alloy through thermodynamic and kinetic analyses based on the CALPHAD approach, using the geometrical representation of phase equilibria and concepts developed to describe internal oxidation. The influence of water vapor on the mechanism and kinetics of formation of the nano-sized precipitates and its role in the overall oxidation process is also considered. T2 - CALPHAD XLV The forty-fifth International Conference on CALPHAD (Computer Coupling of Phase Diagrams and Thermochemistry) CY - Awaji Island, Hyogo, Japan DA - 29.05.2016 KW - Precipitation KW - Internal oxidation KW - CALPHAD KW - Topotactic transformation KW - Microscopy PY - 2016 AN - OPUS4-42156 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sieber, Sarah A1 - Niederleithinger, Ernst A1 - Grohmann, Maria T1 - Image denoising of ultrasonic echo data acquired on concrete N2 - Ultrasonic echo testing has become a common method in civil engineering for the investigation of concrete structures. The detection of inhomogeneities, reinforcing elements and the geometry of the object is required for quality assurance and Inspection. This assessment depends on the quality of ultrasonic images which can be improved by using Reverse Time Migration (RTM) rather than the standard method, Synthetic Aperture Focusing Technique (SAFT). Although RTM provides a better mapping of circular objects and (dipping) reflectors, the image is corrupted by migration noise. To suppress the image noise, we have tested various filter methods in the spatial domain, frequency domain as well as in the curvelet domain on ultrasonic RTM images. We found that either a spatial edge detection filter in combination with a lowpass filter (Laplacian of Gaussian filter) or two lowpass filter with different filter parameters (Difference of Gaussian filter) removed artefacts. An additional smoothing was obtained by applying the first generation curvelet transform after downsampling the image matrix and adding Gaussian noise. The proposed filter scheme is able to suppress RTM noise and enhance the image quality such that the objective interpretation of ultrasonic images for Quality assessment of concrete specimen is simplified. T2 - 76. Jahrestagung der Deutschen Geophysikalischen Gesellschaft CY - Münster, Germany DA - 14.03.2016 KW - Ultrasonic echo technique KW - Reverse-time migration KW - Image Denoising KW - Curvelet Transform PY - 2016 AN - OPUS4-35839 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - John, Sebastian T1 - Lebensdauerabschätzung von Composite-Druckgefäßen / COD-AGE N2 - Ermittlung von Kennwerten und Modelbildung zur Lebensdauerabschätzung von Composite-Druckgefäßen. T2 - 3. Workshop Themenfeld Material CY - Berlin, Germany DA - 12.10.2016 KW - Composite-Druckgefäße KW - Lebensdauer KW - FEM KW - Bruchmechanik PY - 2016 AN - OPUS4-39090 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheuerlein, C. A1 - Rehmer, Birgit A1 - Finn, Monika A1 - Uhlemann, Patrick A1 - Savary, F. A1 - Lackner, F. T1 - Mechanical properties of the HL-LHC 11 Tesla Nb3Sn magnet constituent materials N2 - A test campaign was launched to determine the mechanical properties of the HL-LHC 11 T Nb₃Sn magnet components in order to accurately model the mechanical properties in Finite Element simulations that predict the stress and strain distribution in these magnets. Static and dynamic test methods have been applied for determining elastic materials behavior, and highly accurate Young’s moduli are obtained with the dynamic methods resonance and impulse excitation. These non-destructive methods also enable temperature dependent modulus measurements during in situ heat cycles. T2 - Applied Superconductivity Conference CY - Denver, USA DA - 04.09.2016 KW - Young´s modulus KW - Tensile KW - Compression KW - Temperature dependence PY - 2016 AN - OPUS4-37922 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kathan, Michael A1 - Kovanicek, Petr A1 - Jurissek, Christoph A1 - Senf, Antti A1 - Dallmann, Andre A1 - Thünemann, Andreas A1 - Hecht, Stefan T1 - Photocontrolling imine exchange kinetics to modulate inherent characteristics of self-healing polysiloxane networks N2 - Materials that respond to the environment by changing their properties are critical for developing autonomously adaptive systems. However, to reversibly influence a material's inherent characteristics, such as its ability to self-heal, from distance without continuously expending energy, remains a challenging task. Herein, we report on the modul at ion of imine exchange kinetics by light, manifested in a remote controllable dynamic covalent polymer network. Simple mixing of a commercially available amino-functionalized polysiloxane with small amounts of a photoswitchable diarylethene cross-linker, carrying two aldehyde groups, yields a rubbery material. Its viscoelastic and self-healing properties can be reversibly tuned with everyday light sources, such as sunlight. Our two-component system offers the unique advantage that self-healing takes place continuously without any additives at ambient conditions and is neither dependent on continuous illumination nor does it require recent damage. Overall, our approach allows for the local amplification of intrinsic material properties in a permanent yet reversible fashion. The availability of the inexpensive sta1ting materials on a multi-gram scale, the easy synthesis of the polymer network, and its convenient handling paired with high versatility make our Approach highly applicable to create custom-tailored adaptive materials. T2 - POLYDAYS 2016 CY - Potsdam, Germany DA - 28.09.2016 KW - Self-healing KW - Polymer PY - 2016 AN - OPUS4-37623 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fuhrmann, A. A1 - Göstl, R. A1 - Wendt, R. A1 - Kötteritzsch, J. A1 - Hager, M. D. A1 - Schubert, U. S. A1 - Brademann-Jock, Kerstin A1 - Thünemann, Andreas A1 - Nöchel, U. A1 - Behl, M. A1 - Hecht, S. T1 - Conditional repair by locally switching the thermal healing ability of dynamic covalent polymers ON and OFF with light N2 - Healable materials are able to repair inflicted damages, herin often applied: dynamic covalent polymer networks. We have shown in this study that light of different colors shift the Diels-Alder and retro Diels-Alder crosslinking and decrosslinking equilibrium. This effect was utilized for self-healing of a polymer film. Small-angle X-ray scattering was used to quantifiy the polymeric mesh size on a nanoscale. T2 - Polydays 2016 CY - Potsdam, Germany DA - 28.09.2016 KW - Polymer KW - Small-angle X-ray scattering KW - SAXS KW - Self-healing PY - 2016 AN - OPUS4-37570 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thünemann, Andreas T1 - Characterization of silver nanoparticles in cell culture medium containing fetal bovine serum N2 - Nanoparticles are being increasingly used in consumer products worldwide, and their toxicological effects are currently being intensely debated. In vitro tests play a significant role in nanoparticle risk assessment, but reliable particle characterization in the cell culture medium with added fetal bovine serum (CCM) used in these tests is not available. As a step toward filling this gap, we report on silver ion release by silver nanoparticles, and changes in the particle radii and in their protein corona when incubated in CCM. Particles of a certified reference material (CRM), p1, and particles of a commercial silver nanoparticle material, p2, were investigated. The colloidal stability of p1 is provided by the surfactants polyethylene glycole-25 glyceryl trioleate and polyethylene glycole-20 sorbitan monolaurate, whereas p2 is stabilized by polyvinylpyrrolidone (PVP). Dialysis of p1 and p2 reveal that their silver ion release rates in CCM are much larger than in water. Particle characterization was performed with asymmetrical flow field-flow fractionation (FFF), small-angle X-ray scattering (SAXS), dynamic light scattering (DLS) and electron microscopy. p1 and p2 have similar hydrodynamic radii of 15 nm and 16 nm, respectively. The silver core radii are 9.2 and 10.2 nm. Gel electrophoresis and subsequent peptide identification reveal that albumin is the main corona component of p1 and p2 after incubation in CCM, which consists of Dulbeccos Modified Eagle Medium with 10% fetal bovine serum added. T2 - 6th International Colloids Conference CY - Berlin, Germany DA - 19.06.2016 KW - SAXS KW - Nanoparticle KW - Silver KW - Albumin PY - 2016 AN - OPUS4-36639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mull, Birte A1 - Sauerwald, T. A1 - Richter, Matthias A1 - Horn, Wolfgang A1 - Brödner, Doris A1 - Schultealbert, C. T1 - Development of a reproducibly emitting reference material for volatile organic compounds N2 - Volatile organic compounds (VOC) are ubiquitous in the indoor air, since they emit from materials used indoors. Investigations of these materials are mostly carried out in test chambers under controlled climatic conditions. Quality control of these test chamber measurements is important but there is a lack of commercially available homogenous reference materials. The approach of this study is to dope a supporting material with VOCs, which are then reproducibly released in measurable chamber air concentrations between 30 to 300 µg m ³. From several tested supporting materials vacuum grease (APIEZON M) was selected because of its very low own emissions. First tests were conducted with styrene. For the estimation of the initial emission and the emission over time FEM (finite element methods) modelling was used. Based on this, five samples with a surface of 7 cm2 and a thickness of 12 mm with a content of 1 ‰ styrene were investigated at (23 ± 2) °C and (50 ± 5) % relative humidity in the µ-chamber (3 samples) and 24 L test chambers (2 samples) for 28 days. Air samples were taken after 24 hours, 3, 7, 14, 21 and 28 days on Tenax TA® sorption tubes and analyzed by TD-GC-MS. The area specific emission rate (SERa) was calculated to compare the results from both chamber types. After 24 hours SERa was between 0.8 0.9 µg cm 2 h 1 (3800 4000 µg m 3) for the µ-chamber samples and between 0.9 1.1 µg cm 2 h 1 (300-370 µg m 3) for the 24 L test chamber samples. After 28 days the SERa was at 0.2 µg cm 2 h 1 for all samples. The relative standard deviation of the SERa was between 1 26 %. These results show the applicability of vacuum grease as supporting material and the favored starting concentration range could be achieved in the 24 L test chambers. T2 - Indoor Air 2016, the 14th international conference of Indoor Air Quality and Climate CY - Ghent, Belgium DA - 03.07.2016 KW - Emission test chamber KW - Indoor air KW - Quality assurance KW - Quality control PY - 2016 AN - OPUS4-36823 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hübert, Thomas A1 - Kemnitz, Erhard A1 - Usmani, Shirin A1 - Schlischka, Jörg A1 - Klutzny, Kerstin A1 - de Laval, Yvonne A1 - Plarre, Rüdiger A1 - Krahl, Thoralf A1 - Stephan, Ina T1 - Wood protection with nanoparticles: MgF2 and CaF2 N2 - The potential of alkaline earth metal Fluoride nanoparticles was tested for protection of wood against fungi and termites. These nanoparticles are ideal for wood protection. T2 - School of Analytical Sciences Poster Session CY - Berlin, Germany DA - 06.12.2016 KW - Wood preservation KW - Fluorides KW - Nanoparticles PY - 2016 AN - OPUS4-39141 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Marc Benjamin A1 - Meyer, Susan A1 - Solomun, Tihomir A1 - Kunte, Hans-Jörg A1 - Sturm, Heinz T1 - Electron irradiation of biomolecules under physiological conditions: Experimental realization and microdosimetric calculations N2 - In the last years, secondary low-energy electrons (LEE) emerged as important, if not predominant, reductive pathway in ionizing damage of biomolecules. These electrons are created in copious amount as result of inelastic scattering of high energy radiation at water. Until now, all experiments the quantification of the effects of LEEs on the biomolecular damage was either performed in vacuum with LEE sources or with DNA on surfaces in humid atmosphere. We present a new experimental setup to irradiate biomolecules with electrons under physiological conditions. In combination with monte carlo simulations this setup makes it possible to determine microdosimetric quantities for biomolecules in liquid environment under electron irradiation. This opens up new possibilities in radiation research to access the LEE damage under well defined physiological condition, for more complex systems, such as DNA-Protein complexes and even living cells. T2 - 14th International Congress of the International Radiation Protection Association CY - Cape Town, South Africa DA - 09.05.2016 KW - DNA KW - Dosimetry KW - Microdosimetry KW - Geant4 KW - Low energy electrons KW - Radicals KW - Radiation damage KW - Polymers PY - 2016 AN - OPUS4-36399 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wurzler, Nina A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Emmerling, Franziska A1 - Kunte, Hans-Jörg A1 - Özcan Sandikcioglu, Özlem T1 - Chemical interaction mechanisms of metal reducing bacteria on steel surfaces N2 - Metal reducing bacteria (MRB) are able to utilize various materials such as iron, uranium and manganese as well as many organic compounds as electron acceptors. This process leads to the conversion of Fe(III) containing passive film species to soluble Fe(II) oxides and hydroxides. The reduction process triggers the acceleration of general and local corrosion processes. Electron transfer mechanisms are not yet fully understood. In literature it has been controversially discussed to which extend secreted electron shuttles contribute to the extracellular electron transfer (EET). To understand the chemical and electrochemical interaction mechanisms of MRB with steel surfaces this project combines a variety of in-situ techniques. The changes in oxide chemistry on Fe/steel surfaces in the presence of biomolecules and MRB are under investigation using a newly designed electrochemical cell for in situ XANES (x-ray absorption near edge structure) spectroscopy. Electrochemical quartz crystal microbalance (eQCM) studies support the spectroscopic investigations to gain information about the kinetics of attachment processes and changes in biofilm viscosity. The biofilm structure and composition as well as cell viability are investigated by complementary ex situ spectroscopic and microscopic analysis. Combining spectroscopic techniques and eQCM data with electrochemical measurements, biological processes and the resulting degradation of steel surfaces can be observed in a non-destructive manner. Selecting model systems and a defined biological medium allows the determination of individual effects of diverse surface and environmental parameters. The fundamental understanding of bacterial attachment mechanisms and initial steps of biofilm formation will contribute to the development of new antifouling strategies. T2 - 12th International Conference on Biology and Synchrotron Radiation CY - San Francisco, CA, USA DA - 21.08.2016 KW - Microbially influenced corrosion (MIC) KW - Metal reducing bacteria KW - XANES KW - Electrochemistry PY - 2016 AN - OPUS4-37238 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Veliz Montes, Cinthya A1 - Bottari, G. A1 - Trukina, O. A1 - Torres, Tomás A1 - Schneider, Rudolf T1 - Unsubstituted, covalently-linked phthalocyanine-C60 fullerene dyads N2 - Were prepared four unsubstituted Pc - C60 fullerene systems, using two different synthetic strategies, via Prato (1,3 - dipolar cycloaddition) or Bingel reactions. The precursor Pcs 1 and 2 were successfully synthesized by cyclotetramerization reaction between TBDPS - protected and unsubstituted phthalonitriles. The surface studies are currently ongoing. T2 - PcsTT2016 Symposium CY - Elche, Spain DA - 27.01.2016 KW - Fullerene KW - Phthalocyanine PY - 2016 AN - OPUS4-38556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph A1 - Yevtushenko, Oleksandra A1 - Oelrich, Gerhard A1 - Hattendorf, H. T1 - Hochlegierte metallene Werkstoffe in Salzschmelzen N2 - In letzter Zeit kommen immer mehr alternative Energiequellen als Ersatz fossiler Brennstoffe zum Einsatz, so auch die Solarthermie. Jedoch sind die Betriebsbedingungen aufgrund der chemischen Zusammensetzung der Wärmeträgermedien und herrschenden Temperaturen extrem hinsichtlich Korrosion. Da die Kraftwerke bei maximaler Lebensdauer ökonomisch vertretbar sein müssen, ist eine Werkstoffauswahl basierend auf Voruntersuchungen notwendig, um einen sicheren und verlässlichen Betrieb dieser Anlagen zu gewährleisten. Die Werkstoffauswahl hängt von der Betriebstemperatur eines Kraftwerks bzw. der chemischen Zusammensetzung des Wärmeträgermediums ab. In hochkorrosiven Umgebungen werden aufgrund ihrer sehr guten Korrosionsbeständigkeit Nickelbasislegierungen nicht nur für stark korrosiv beanspruchte Bauteile als die Lösung angesehen. Jedoch kann es durchaus beständigkeitsbedingte Einschränkungen für den Einsatz geben, wofür die hier vorgestellten Ergebnisse dienen sollen. In diesem Beitrag wird die Beständigkeit ausgewählter hochlegierter Werkstoffe (inklusive einer neuentwickelten Legierung in einer Nitrat-Salzschmelze (60 % NaNO3/40 % KNO3) vorgestellt, die mittels elektrochemischer Messungen und Auslagerungsversuchen ermittelt wurde. T2 - 48. Kraftwerkstechnisches Kolloquium CY - Dresden, Germany DA - 18.10.2016 KW - Örtliche Korrosion KW - Nickelbasislegierungen KW - Solarenergie KW - Erneuerbare Energien KW - Elektrochemische Charakterisierung PY - 2016 AN - OPUS4-37754 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph A1 - Yevtushenko, Oleksandra A1 - Bettge, Dirk A1 - Le, Quynh Hoa A1 - Carrillo Salgado, I. T1 - Korrosion von Rohrleitungswerkstoffen durch Kondensationseffekte infolge von SO2- und NO2-Begleitstoffen in CO2 N2 - Derzeit wird der Einsatz metallener Werkstoffe in CCU-/CCS-Anlagen hinsichtlich deren Korrosionsbeständigkeit und eine eventuell daraus resultierende Herausforderung diskutiert. Während des CO₂-Transportes vom Abscheide- zum Injektionsort kann es aufgrund der den CO₂-Strom begleitenden Beimengungen, wie Wasser, O₂, SOₓ , NOₓ , Temperaturschwankungen durchaus zu Kondensationseffekten und daraus resultierenden Schäden kommen. Es konnte gezeigt werden, dass die sich möglicherweise innerhalb einer CO₂-Rohrleitung bildenden Kondensate infolge von Begleitstoffen wie SO2 und NO2 eine viel korrosivere Wirkung auf Rohrleitungswerkstoffe entfalten, als in reinem CO₂. T2 - 48. Kraftwerkstechnisches Kolloquium CY - Dresden, Germany DA - 18.10.2016 KW - CO2-Korrosion KW - Edelstahl KW - Chromstahl KW - CCUS KW - Kondensation PY - 2016 AN - OPUS4-37753 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph A1 - Keserović, Amela A1 - Sobetzki, Joana A1 - Sarmiento Klapper, Helmuth A1 - Dimper, Matthias T1 - Evaluation of metallic materials for geothermal applications N2 - Since geothermal wells are a feasible energy source to replace fossil fuel supply, many technologies have been developed to take advantage of geothermal energy. Nevertheless, service conditions in geothermal facilities are due to the chemical composition of hydrothermal fluids and temperatures, in many cases, extreme in terms of corrosion. Therefore, materials selection based on preliminary material qualification is essential to guarantee a secure and reliable operation of the facilities. The corrosion behavior of different high-alloyed metals including Duplex and austenitic stainless steels as well as a nickel alloy have been evaluated in artificial geothermal fluids simulating the conditions in some locations with geothermal potential in Germany as well as two sites in Indonesia. The suitability of carbon steel 25CrMo4, stainless steels X2CrNiMo17-12-2, X2CrNiMo-22-5, X2CrNiMoCuWN25-7-4 and super austenitic steel X1CrNiMoCu32-28-7 in these geothermal fluids obtained by electrochemical measurements and exposure tests is limited. The nickel alloy NiCr23Mo16Al shows an excellent corrosion resistance against pitting corrosion. Excluding its high cost, it is a very good alternative to be used in the construction of geothermal facilities having highly saline brines. Stainless and Duplex steels exhibit a limited corrosion resistance concerning pitting and crevice corrosion. Beside of the higher alloyed materials, also the lowalloyed steel 25CrMo4 could be employed as a constructional material for the geothermal power plant in stagnant highly acidic non Saline environments, as long as the wall thickness of the material vs. corrosion rate is taken into account. T2 - European Geothermal Congress CY - Strasbourg, France DA - 19.09.2016 KW - Localized corrosion KW - Stainless steel KW - Ni-based alloy KW - Geothermal energy PY - 2016 AN - OPUS4-37751 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wurzler, Nina A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Emmerling, Franziska A1 - Kunte, Hans-Jörg A1 - Özcan Sandikcioglu, Özlem T1 - Investigation of the mechanisms of microbially induced corrosion on Fe/steel surfaces N2 - The role of metal reducing bacteria (MRB) in corrosion is being controversially discussed in the literature. They can utilize metals including iron, uranium and manganese as well as many organic compounds as electron acceptors. The reduction of Fe(III) compounds to soluble Fe(II) species leads to the destruction of passive films on steel, resulting in acceleration of general and local corrosion processes. Recent research shows that the secretion of electron shuttles like riboflavins also contribute to the extracellular electron transfer (EET). The aim of this project is to understand the chemical and electrochemical interaction mechanisms of MRB with steel surfaces by means of combined in situ techniques. An electrochemical XANES (x-ray absorption near edge spectroscopy) cell has been designed to study the changes of passive film chemistry in the presence of biomolecules and MRB. Electrochemical quartz crystal microbalance (eQCM) is used for studying the kinetics of bacterial cell attachment and diffusion of biomolecules in model biofilms. In situ investigations are complemented by ex situ spectroscopic and microscopic analysis to investigate the biofilm structure, composition and cell viability. Via the combination of electrochemical methods with spectroscopic techniques and QCM we are able to follow biological processes and resulting degradation of steel surfaces in a non-destructive manner. The selection of model systems and a defined biological medium allows the identification of the effects of individual surface and environmental parameters. The fundamental understanding of bacterial attachment mechanisms and initial steps of biofilm formation will contribute to the development of new antifouling strategies. T2 - Electrochemistry 2016 CY - Goslar, Germany DA - 26.09.2016 KW - MIC KW - Microbiologically influenced corrosion KW - XANES KW - Electrochemistry PY - 2016 AN - OPUS4-38199 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kabelitz, Anke A1 - de Oliveira Guilherme Buzanich, Ana A1 - Reinholz, Uwe A1 - Radtke, Martin A1 - Bienert, Ralf A1 - Schulz, K. A1 - Kraehnert, R. A1 - Emmerling, Franziska T1 - Time-resolved studies on the formation of maghemite nanoparticles combining fast-XANES and SAXS N2 - Iron oxide nanoparticles find application in different areas like sensing, magnetic storage media, and biomedicine, due to their magnetic properties and environment-friendliness. In the present contribution, we report on the in situ investigation of an iron oxide nanoparticle synthesis by coupled X-ray absorption near-edge structure (XANES) and small-angle X-ray scattering (SAXS). The combination provides simultaneously information about the size of particles (SAXS) and on the oxidation state and the local structure of the iron atoms (XANES). The co-precipitation synthesis was exemplary studied, using a stabilization agent to decelerate the fast precipitation of the iron oxides. This allows to detect intermediates in situ. The measurements were performed using a custom-made acoustic levitator as sample holder. From the data, a mechanism was derived indicating different phases of particle Formation and oxidation state changes. T2 - The European Materials Research Society-Spring Meeting 2016 CY - Lille, France DA - 01.05.2016 KW - Iron oxide nanoparticles KW - SAXS KW - XANES KW - Time-resolved PY - 2016 AN - OPUS4-36351 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -