TY - JOUR A1 - Kranzmann, Axel A1 - Neddemeyer, Torsten A1 - Ruhl, Aki Sebastian A1 - Hünert, Daniela A1 - Bettge, Dirk A1 - Oder, Gabriele A1 - Saliwan Neumann, Romeo T1 - The challenge in understanding the corrosion mechanisms under oxyfuel combustion conditions N2 - Basic research on the corrosive effect of flue gases has been performed at the BAM Federal Institute for Materials Research and Testing (Germany). Conditions at both high and low temperatures were simulated in specially designed experiments. Carburization occured in flue gases with high CO2 content and temperatures higher than 500 °C. In SO2 containing flue gases sulphur was detected in the oxide scale. At lower temperatures no corrosion was observed when gases with low humidity were investigated. Humidity higher than 1500 ppm was corrosive and all steels with Cr contents lower than 12% revealed corroded surfaces. At low temperatures below 10 °C a mixture of sulphuric and nitric acid condensed on metal surfaces. Acid condensation caused severe corrosion. Humidity, CO2, O2, and SO2 contents are the important factors determining corrosion. Below 300 °C acid condensation is the primary reason for corrosion. Low humidity and low temperatures are conditions which can be expected in the CO2 separation and treatment process. This work includes major conditions of the flue gas and CO2 stream in CCS plants and CCS technology. KW - Coal KW - Oxyfuel power plant KW - Corrosion KW - Carburization KW - Sulphur KW - Sulphuric acid PY - 2011 DO - https://doi.org/10.1016/j.ijggc.2011.05.029 SN - 1750-5836 VL - 5 IS - Supplement 1 SP - S168 EP - S178 PB - Elsevier CY - New York, NY [u.a.] AN - OPUS4-24705 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klapper, Helmuth Sarmiento A1 - Burkert, Andreas A1 - Burkert, Annette A1 - Lehmann, Jens A1 - Villalba, A.L. T1 - Influence of surface treatments on the pitting corrosion of type 304 stainless steel by electrochemical noise measurements N2 - Surface treatments usually are used to modify the appearance and properties of stainless steel surfaces. Simultaneously, the corrosion resistance of the stainless steel surface being related intrinsically to the spontaneous formation of a passive layer also will be affected. In this respect, the influence of different surface treatments on the corrosion resistance of Type 304 (UNS S30400) stainless steel to pitting corrosion has been evaluated by means of potentiostatic electrochemical noise measurements and surface characterization. Typical industrial treatments including mechanical grinding, glass blasting, and pickling were taken into account. Additionally, special consideration was put on the effect of aging conditions of the passive layer after surface treatments, in particular on the relative humidity. Benefits and limitations of the different applied surface treatments concerning protectiveness of the stainless steel surface were determined and discussed. KW - Corrosion KW - Electrochemical noise KW - Pitting corrosion KW - Stainless steel KW - Surface treatment PY - 2011 DO - https://doi.org/10.5006/1.3613641 SN - 0010-9312 SN - 1938-159X VL - 67 SP - 075004-1 EP - 075004-13 PB - National Association of Corrosion Engineers CY - Houston, Tex. AN - OPUS4-24247 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pfennig, Anja A1 - Kranzmann, Axel T1 - Reliability of pipe steels with different amounts of C and Cr during onshore carbon dioxide injection N2 - During the compression of emission gasses into deep geological layers (Carbon Dioxide Capture and Storage, CCS) CO2-corrosion will become a relevant safety issue. The reliability of the steels used at a geological onshore CCS-site in the Northern German Bassin 42CrMo4 (1.7225, AISI 4140) used for casing, and the injection pipe steels X46Cr13 (1.4034, AISI 420 C), X20Cr13 (1.4021, AISI 420 J) as well as X35CrMo17 (1.4122) is demonstrated in laboratory experiments. Samples were kept in a synthetic aquifer environment at T = 60 °C. This corrosive environment is then saturated with technical CO2 at a flow rate of 3 l/h. Microstructures were characterized by X-ray diffraction, light microscopy, scanning electron microscopy, and energy dispersive X-ray analysis, after a series of heat treatments (700 h to 2 years). The non-linear isothermal surface corrosion behaviour of the steels reveals surface corrosion rates around 0.1–0.8 mm/year, when obtained by mass gain. Severe pit corrosion (pit heights ca. 4.5 mm) are only located on the injection pipe steels. Main phases of the continuous scales are siderite FeCO3 and goethite α-FeOOH. The formation of the non-protective layer is likely to form via a transient Fe(OH)2-phase. KW - Steel KW - Pipe KW - Corrosion KW - Carbonate layer KW - CO2-injection KW - CO2-storage CCS PY - 2011 DO - https://doi.org/10.1016/j.ijggc.2011.03.006 SN - 1750-5836 VL - 5 IS - 4 SP - 757 EP - 769 PB - Elsevier CY - New York, NY [u.a.] AN - OPUS4-25533 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Westin, E. M. A1 - Stelling, Karen A1 - Gumenyuk, Andrey T1 - Single-pass laser-GMA hybrid welding of 13.5 mm thick duplex stainless steel N2 - Single-pass solid-state laser welding of plates in the thickness range of 10 to 20 mm became possible with the invention of the fibre laser. This new technique provides excellent beam quality at powers as high as 20 kW or more, and has proved applicable in several industrial applications. By replacing conventional methods with the fibre laser, it is possible to avoid multiple-pass welding that requires time-consuming bevelling. The high energy density of the fibre laser beam also reduces the heat input and consequently the distortion. However, the rapid solidification and cooling associated with laser welding can cause imbalance of the microstructure of duplex stainless steel weldments, where excessively high ferrite contents may reduce the corrosion resistance and the ductility of the material. The solution is normally to add nickel-based filler wire and to increase the heat input. By using a hybrid welding process where the laser beam and the gas metal arc (GMA) process act in a common process zone, filler metal can be added to the molten pool at higher heat input and at the same time, higher welding speed and deeper penetration can be achieved. In this work, 13.5 mm thick 2205 (EN 1.4462, UNS S31803) was fibre laser-GMA hybrid welded in a single-pass using 14 kW of laser power and ISO 22 9 3 N L as filler wire for the GMA process. The resulting welds were free from defects, with smooth surfaces and full penetration. The investigation examines the weld metal microstructure and the effect on corrosion resistance and mechanical properties. The option to add nickel foil, when hybrid welding, was also investigated, as comparison, and the effect on austenite formation was evaluated. KW - Austenite KW - Combined processes KW - Corrosion KW - Duplex stainless steels KW - Laser welding KW - Microanalysis KW - Weld metal KW - Weldability KW - Welding PY - 2011 SN - 0043-2288 SN - 1878-6669 VL - 55 IS - 1/2 / IIW-2028-09 SP - 39 EP - 49 PB - Springer CY - Oxford AN - OPUS4-23476 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pfennig, Anja A1 - Linke, Barbara A1 - Kranzmann, Axel T1 - Corrosion behaviour of pipe steels exposed for 2 years to CO2 -saturated saline aquifer environment similar to the CCS-site Ketzin, Germany N2 - When emission gasses are compressed into deep geological layers (CCS) CO2-corrosion of injection pipe steels is a relevant safety issue. The reliability of the steels used at the geological onshore CCS-site at Ketzin, Germany, is demonstrated in 2 years laboratory experiments under an equivalent corrosive environment at ambient pressure (T=60 °C, aquifer water, CO2-flow rate of 3 l/h). Corrosion kinetics and microstructures were characterized using samples of the heat treated steel 42CrMo4 (casing), and samples of the martensitic stainless steel X46Cr13 (injection). KW - Steel KW - Pipeline KW - Corrosion KW - CCS KW - CO2-storage PY - 2011 SN - 1876-6102 VL - 4 SP - 5122 EP - 5129 PB - Elsevier CY - Amsterdam AN - OPUS4-23621 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nofz, Marianne A1 - Sojref, Regine A1 - Dreßler, Martin A1 - Hünert, Daniela A1 - Dörfel, Ilona A1 - Saliwan Neumann, Romeo T1 - Sol-gel alumina coatings for high-temperature corrosion protection of Ni-base alloy SC16 in water vapour containing atmosphere N2 - Alumosols in combination with well dispersed corundum were successfully used to form up to 2.5 ìm thick coatings on the Ni-base alloy SC16. These coatings withstood heat treatments at 700 °C in a water vapour containing atmosphere. The heat treatment caused formation of delta-alumina in the coating and diffusion of chromium and titanium into the coating. KW - Alumina KW - Coating KW - Sol-gel KW - Corrosion KW - Protection PY - 2009 SN - 0020-5214 VL - 58 IS - 4 SP - 192 EP - 195 PB - DVS-Verl. CY - Düsseldorf AN - OPUS4-19726 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eichler, Thorsten A1 - Isecke, Bernd A1 - Bäßler, Ralph T1 - Investigations on the re-passivation of carbon steel in chloride containing concrete in consequence of cathodic polarisation N2 - Although the complex changes at the steel-concrete interface due to cathodic polarisation are widely acknowledged to have a beneficial influence concerning the cathodic protection (CP) of steel in concrete, some questions concerning the repassivation of carbon steel in consequence of cathodic polarisation are still not satisfactorily clarified. In the recent literature, some indications are presented that repassivation occurs after a certain time of polarisation. Therefore, the investigations discussed in this paper aim to clarify, to what extent the re-passivation of carbon steel due to cathodic polarisation occurs, and if the ennoblement of OCP is a sufficient indication for repassivation. In a first step, the corrosion state of five nominal equal test specimens was determined by electrochemical impedance spectroscopy (EIS). After determining the initial corrosion state by evaluating the charge transfer resistance and the polarisation resistance, respectively, the specimens were polarised cathodically. Impedance data were recorded before, during and after polarisation. The impedance data were evaluated by equivalent circuit fitting with special attention to charge transfer resistances and the impact of diffusion on the corrosion and polarisation behaviour. The results indicate that the reduction of oxides and oxygen diffusion during cathodic polarisation has strong impact on the systems behaviour and that repassivation effects occur after switching off the polarisation current and during depolarisation, respectively. KW - Steel in concrete KW - Cathodic protection KW - Pitting corrosion KW - Mild steel KW - Electrochemical impedance spectroscopy KW - Chlorides KW - Corrosion KW - High alkaline environment KW - Reinforced concrete KW - Unalloyed steel KW - Passivity PY - 2009 DO - https://doi.org/10.1002/maco.200805142 SN - 0947-5117 SN - 1521-4176 VL - 60 IS - 2 SP - 119 EP - 129 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-18808 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pfennig, Anja A1 - Kranzmann, Axel T1 - Effects of saline aquifere water on the corrosion behaviour of injection pipe steels 1.4034 and 1.7225 during exposure to CO2 environment N2 - CO2-corrosion of injection pipe steels is a relevant safety issue when emission gasses are compressed in deep geological layers (CCS). The reliability of the steels used at the geological onshore CCS-site at Ketzin, Germany, is demonstrated in laboratory experiments under an equivalent corrosive environment (T=60 °C,p=1-60 bar, aquifer water, CO2-flow rate of 3 l/h, 700 h–8000 h heat treatment). Corrosion kinetics and microstructures were characterized using samples of the heat treated steel 1.7225 (AISI 4140, 42CrMo4) used for casing, and samples of the martensitic stainless injection-pipe steel 1.4034 (AISI 420, X46Cr13). KW - Steel KW - Pipeline KW - Corrosion KW - Carbonate layer KW - CCS KW - CO2-injection KW - CO2-storage PY - 2009 DO - https://doi.org/10.1016/j.egypro.2009.02.080 SN - 1876-6102 VL - 1 IS - 1 SP - 3023 EP - 3029 PB - Elsevier CY - Amsterdam AN - OPUS4-19393 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mikó, Annamária A1 - Erning, Johann Wilhelm A1 - Schlerkmann, H. A1 - Mathiesen, T. T1 - Comparative investigation of stainless steels used in drinking water distribution systems N2 - Five stainless steel alloys were tested and compared to find a test method for the qualification of stainless steel used in drinking water systems. Determination of the pitting/critical potentials from the conventional cyclic polarization results was shown to be difficult when stainless steels have high Mo and Cr content. The electrochemical impedance data indicated that results received with the conventional methods do not necessarily reflect the steady state. The low frequency time constant determined from the impedance measurements showed that the anodic polarization should be conducted with very slow scan rate to get information about the mechanism. The steady state investigations were compared with the conventional electrochemical results to propose an electrochemical-based route as a standard qualification method. The qualification method was tested to be valid by a European round-robin-test. KW - Drinking water KW - Stainless steel KW - Passivity KW - Corrosion KW - Test method for stainless steel PY - 2009 DO - https://doi.org/10.1016/j.electacta.2009.08.003 SN - 0013-4686 SN - 1873-3859 VL - 54 IS - 28 SP - 7507 EP - 7513 PB - Elsevier Science CY - Kidlington AN - OPUS4-20132 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pfennig, Anja A1 - Bäßler, Ralph T1 - Effect of CO2 on the stability of steels with 1% and 13% Cr in saline water N2 - In engineering storage sites for Carbon Sequestration the CO2-induced corrosion of injection pipe steels is a relevant safety issue when emission gasses are compressed in deep geological layers. The reliability of the steels suitable for the geological onshore CCS-site (Carbon Capture and Storage) at Ketzin, Germany, is demonstrated in laboratory experiments in equivalent corrosive environment (T = 60 °C, p = 1–60 bar, aquifer water, CO2-flow rate of 3 L/h, 700–8000 h exposure time). Corrosion kinetics and microstructures were characterized using specimens of the heat treated steel 42CrMo4 (1.7225) used for casing, and specimens of the martensitic stainless injection-pipe steel X46Cr13 (1.4034). KW - Corrosion KW - Layer products KW - Kinetics KW - Steel KW - Carbon Capture and Storage KW - Low alloyed steel KW - Stainless steel KW - SEM KW - Pitting corrosion KW - Kinetic parameters PY - 2009 DO - https://doi.org/10.1016/j.corsci.2009.01.025 SN - 0010-938X VL - 51 IS - 4 SP - 931 EP - 940 PB - Elsevier CY - Orlando, Fla. AN - OPUS4-19144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -