TY - CONF A1 - Nolze, Gert A1 - Saliwan Neumann, Romeo A1 - Buchheim, Michaela T1 - Microstructure investigations of iron meteorites by EBSD and EDS analyses N2 - Meteorites are a unique and inspiring material for microstructural studies because if their very specific genesis. Iron meteorites have been formed under unimaginable cooling rates of a few ten Kelvins per million years so that the observable transformation of the formerly huge Fe-Ni single crystals of taenite occurred under nearly-equilibrium conditions. Octahedrites (meteorites having a Ni content between 6...15%) are characterized by ribbons of the low-temperature Fe-Ni phase kamacite separated by rims of residual taenite. This very specific feature is known as Widmanstaetten structure and has been investigated by synchrotron radiation in order to cover a higher volume fraction for a statistically relevant description of orientation relationships. However, plessite – a microstructure mainly consisting of the same phases – reflects the orientation relationship between kamacite and taenite as well. For their characterization, a scanning electron microscope is very suitable in order to investigate crystal orientations or identify phases. Despite the apparently ideal formation circumstances of iron meteorites, Ni concentration profiles prove non-equilibrium conditions. Combined EDS (energy dispersive spectroscopy) and EBSD (electron backscatter diffraction) measurements at a selected plessitic region of the Cape York iron shows that a correlation exists between Ni-concentration and the locally detected orientation relationship. T2 - 15th European Microscopy Congress CY - Manchester, UK DA - 16.09.2012 KW - Phase identification KW - Corrosion KW - Chloride KW - Dermbach PY - 2012 SP - 90 AN - OPUS4-37775 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pfennig, Anja A1 - Kranzmann, Axel T1 - Borehole integrity of austenitized and annealed pipe steels suitable for carbon capture and storage (CCS) N2 - Properties of pipe steels for CCS (carbon capture and storage) technology require resistance against the corrosive environment of a potential CCS-site (heat, pressure, salinity of the aquifer, CO2-partial pressure). The influence of austenitzing in heat treatment routines of two different injection pipe Steels (1.4034, X46Cr13 and 1.4021, X20Cr13) was evaluated. Steel coupons were austenitized at different temperatures (900- 1050 °C) for different lengths of time (30-90 min) before quenching and annealing prior to long term corrosion experiments (60°C, 100 bar, artificial brine close to a CCS-site in the Northern German Basin, Germany). In general, fewer pits are found on X46Cr13. Comparing steels with 13% chromium each the higher carbon content of X46Cr13 (0.46% C) results in a lower number of pits compared to X20Cr13 (0.20% C). It is found that neither the carbon content of the steels nor austenitizing temperature has much influence, but local corrosion behaviour is most susceptible towards austenitzing time. T2 - 2016 APCBEES Pattaya Conference CY - Pattaya, Thailand DA - 23.01.2016 KW - Heat Treatment KW - CCS KW - CO2 KW - Corrosion KW - Steel PY - 2016 AN - OPUS4-38444 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pfennig, Anja A1 - Kranzmann, Axel T1 - Borehole integrity of austenitized and annealed pipe steels suitable for carbon capture and storage (CCS) N2 - Properties of pipe steels for CCS (carbon capture and storage) technology require resistance against the corrosive environment of a potential CCS-site (heat, pressure, salinity of the aquifer, CO2-partial pressure). The influence of austenitzing in heat treatment routines of two different injection pipe steels (1.4034, X46Cr13 and 1.4021, X20Cr13) was evaluated. Steel coupons were austenitized at different temperatures (900-1050 °C) for different lengths of time (30-90 min) before quenching and annealing prior to long term corrosion experiments (60°C, 100 bar, artificial brine close to a CCS-site in the Northern German Basin, Germany). In general, fewer pits are found on X46Cr13. Comparing steels with 13% chromium each the higher carbon content of X46Cr13 (0.46% C) results in a lower number of pits compared to X20Cr13 (0.20% C). It is found that neither the carbon content of the steels nor austenitizing temperature has much influence, but local corrosion behaviour is most susceptible towards austenitzing time. T2 - 6th International Conference on Future Environment and Energy (ICFEE 2016) CY - Pattaya, Thailand DA - 23.01.2016 KW - CCS KW - CO2 KW - Corrosion KW - Steel KW - Heat treatment PY - 2016 SP - 9 EP - 14 AN - OPUS4-38980 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Armatys, Kamila A1 - Adamczyk, Burkart A1 - Adam, Christian A1 - Pflumm, R. A1 - Galetz, M. C. T1 - Corrosion and abrasion resistant protective coatings for biomass combustion N2 - The environmental concerns about availability of fossil fuels and greenhouse gas effect increase and alternative renewable fuels for power plants are gaining significantly of importance. 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. This paper presents the principle of experimental methods developed for the investigations of high temperature corrosion combined with abrasion in thermochemical processes with high hydrochloric acid concentrations like during biomass combustion. The aim of the presented investigation methods it 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 - Corrosion KW - Coatings PY - 2016 SP - 1 EP - 9 CY - Proceedings in Young Researchers Conference: Energy Efficiency & Biomass 2016 AN - OPUS4-35714 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Yevtushenko, Oleksandra A1 - Bettge, Dirk T1 - On the corrosion mechanism of CO2 transport pipeline steels caused by impurities: roles of each impure components and benchmarks N2 - Carbon Capture, Utilization and Storage (CCUS) has been proposed as a promising technology for the mitigation of CO2 emissions into the atmosphere from fossil-fuel-operated power generation plants. As the reliability and cost effectiveness of the pipeline transport network is crucial to the overall operability and resilience of the CCUS system, it is vital to realize the possible corrosion risks of the employed pipeline steels corresponding to the impurity level of the gas source. Recent studies have shown that even the high alloyed materials might be susceptible to general and/or localized corrosion by the condensates forming from the impurities such as SOx, NOx, CO, O2 and water [1]. Up to now, however, there is no regulation procedure which defines the maximum acceptable level of impurities and the combination of them for each employed pipeline steels. Herein, systematic experiment series were conducted by mixing pure CO2 gas with varying concentration of each impurity and with the varying combination of them. Each time, the mixture was then fed (1 L/min) into the reactor containing 12 specimens for 120-600 h at 5°C (to simulate the sub-level pipeline transport). The resulted condensate was collected and analyzed by ionic chromatography and atomic absorption spectroscopy to determine the chemical composition. In this study, the “worst-case scenario” gas mixture, containing 2.5 % H2O, 1.8 % O2, 1000 ppm NO2, and 220 ppm SO2 as impurities, resulted in the condensate containing H2SO4 0.114 M and HNO3 0.0184 M (pH 2.13). This “original” condensate was then re-produced to carry out exposure tests and electrochemical characterization including corrosion potentials and impedance spectroscopy in CO2 saturated condition for 7-14 days at the same temperature. The corrosion rate was also measured by mass loss method. We can conclude that, at the initial stage, HNO3 plays the dominant role in Fe dissolution process, while H2SO4 is responsible for the pit initiation followed by pitting corrosion. Future studies will be focused on the combination effect from the impurities and the exposure test under the regularly changing condensate to mimic the real CO2 pipeline system. T2 - Eurocorr 2016 CY - Montpellier, France DA - 11.09.2016 KW - Carbon capture utilization KW - CO2 KW - Pipeline transport KW - Condensation KW - Corrosion PY - 2016 SP - paper 69810, 1 EP - 2 PB - EFC CY - Montpellier AN - OPUS4-37747 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nützmann, Kathrin A1 - Kranzmann, Axel A1 - Stephan-Scherb, Christiane T1 - Real time investigation of high temperature corrosion of ferritic alloys in SO2-gas N2 - The ageing of Fe-Cr model alloys in 0.5 % SO2 and 99.5 % Ar atmosphere was investigated to aim in a fundamental and systematic analysis of the combined oxidation and sulfidation mechanism. The crystallization and reaction paths for oxide and sulfide formation were followed in-situ by energy dispersive X-ray diffraction (EDXRD) in an early stage of corrosion (30 s – 24 h). For this technique, high energetic white synchrotron X-ray radiation (10-100 keV) was used as radiation source. Diffraction pattern were collected continuously in an early stage of corrosion up to 24 h during the complete ageing experiment. The crystalline phases, growing on top of the coupons, were identified directly via their specific dhkl values. The evolution of the extracted integral intensities of specific reflections of the corrosion products as a function of time access direct information about the kinetics of the nucleation and growth. The results presented here show for iron with 2 wt% Cr wuestite formation first. Wuestite vanishes after 10 min of reaction only and magnetite and hematite appear. Magnetite formation proceeds simultaneously with sulfide formation. Sulfides growth proceeds after an incubation time, which differs for low alloyed (2 wt% Cr) and high alloyed (9 wt% Cr) material. T2 - EUROCORR CY - Prague, Czech Republic DA - 03.09.2017 KW - In situ KW - Diffraction KW - Corrosion PY - 2017 SP - 79746 AN - OPUS4-44708 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pfennig, Anja A1 - Kranzmann, Axel T1 - Borehole integrity of austenitized and annealed pipe steels suitable for carbon capture and storage (CCS) N2 - Properties of pipe steels for CCS (carbon capture and storage) technology require resistance against the corrosive environment of a potential CCS-site (heat, pressure, salinity of the aquifer, CO2-partial pressure). The influence of austenitzing in heat treatment routines of two different injection pipe steels (1.4034, X46Cr13 and 1.4021, X20Cr13) was evaluated. Steel coupons were austenitized at different temperatures (900- 1050 °C) for different lengths of time (30-90 min) before quenching and annealing prior to long term corrosion experiments (60°C, 100 bar, artificial brine close to a CCS-site in the Northern German Basin, Germany). In general, fewer pits are found on X46Cr13. Comparing steels with 13% chromium each the higher carbon content of X46Cr13 (0.46% C) results in a lower number of pits compared to X20Cr13 (0.20% C). It is found that neither the carbon content of the steels nor austenitizing temperature has much influence, but local corrosion behaviour is most susceptible towards austenitzing time. T2 - International Conference on Future Environment and Energy CY - Pattaya, Thailand DA - 23.01.2016 KW - Corrosion KW - CCS KW - Carbon storage KW - Aquifer KW - Austenitizing PY - 2017 SP - Article A0005, 213 EP - 219 AN - OPUS4-41854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heyn, A. A1 - Müller, Thoralf A1 - Balzer, M. A1 - Fenker, M. A1 - Kappl, H. T1 - Corrosion protection mechanisms of TiMgN hard coatings on steel N2 - . Hard coated steel components are used in a wide application range, mostly for protective, wear resistant and decorative purposes. Despite of these coatings being regarded as relatively dense, there is always a high risk of localized corrosion when a coated low alloyed steel component encounters a surrounding high humidity atmosphere or even an aqueous medium. An approach to enhance the corrosion properties is the addition of magnesium to physical vapor deposited hard coatings, like TiN. It has been found that there is a remarkable increase in corrosion resistance in dependence of magnesium content of the TiMgN coating and its surface properties. In this work the authors will explain the underlying corrosion protection mechanisms by means of electrochemical and analytical studies. The positive impact of magnesium in the coating relates on its preferred dissolution vs. steel. This causes the potential to shift to more negative direction with respect to the steel substrate and additionally leads to a temporarily passivation of the steel due to alkalization of the surrounding electrolyte by formation of magnesium hydroxide. T2 - 20. Werkstofftechnisches Kolloquium CY - Chemnitz, Germany DA - 14.03.2018 KW - Corrosion KW - Titanium nitride KW - PVD hard coating KW - Magnesium PY - 2018 SN - 978-3-00-058901-0 SN - 1439-1597 VL - 72 SP - 74 EP - 83 PB - Eigenverlag CY - Chemnitz AN - OPUS4-44526 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. Werkstofftechnisches Kolloquium CY - Chemnitz, Germany DA - 14.03.2018 KW - Corrosion KW - Corrosion resistance KW - Corrosion testing KW - EPR KW - Heat treatment KW - Stainless steel PY - 2018 SN - 978-3-00-058901-0 SN - 1439-1597 VL - 72 SP - 277 EP - 284 PB - Eigenverlag CY - Chemnitz AN - OPUS4-44558 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, Gabriela A1 - Bäßler, Ralph A1 - Roth, C. T1 - Polyaniline/silicon dioxide containing coating for use in artificial geothermal brines N2 - Geothermal brine is a complex system containing a wide variety of dissolved salts resulting from the condition s in a geothermal well. These fluids lead to corrosion in pipes and other parts of geothermal system construction and necessitate intense research efforts in finding new suitable materials. Carbon steel is susceptible to corrosion in geothermal brine especially when it is exposed to a high temperature and high-pressure medium, which is considered to be an aggressive environment. An artificial geothermal water, bas ed on a brine composition found in Indonesia, was used to investigate the performance of high alloyed materials. The electrolyte has pH 4 and contains 1,500 mg/l Cl-, 20 mg/l SO4 2-, 15 mg/l HCO3 -, 200 mg/l Ca 2+, 250 mg/l K+, and 600 mg/l Na+. In order to protect the bare material in geothermal application, it is necessary to either use high alloyed material s or coatings. In this research, a coating system consisting of polyaniline and silicon dioxide was investigated regarding its behavior to protect carbon steel. In detail, the effect of SiO2 and polyaniline (PANi) addition was evaluated by exposure and electrochemical tests for 7 days, i.e. electrochemical impedance spectroscopy (EIS) and open circuit potential (OCP ) at room temperature and 150 °C with 1 MPa pressure . T2 - NACE International Annual Corrosion Conference CY - Phoenix, AZ, USA DA - 15.04.2018 KW - Geothermal KW - Coating KW - SiO 2 KW - Polyaniline KW - Corrosion PY - 2018 SP - 10708, 1 EP - 14 PB - Omnipress CY - Houston AN - OPUS4-44916 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -