TY - JOUR A1 - Mietz, Jürgen T1 - Investigations on hydrogen-induced embrittlement of quenched and tempered prestressing steels N2 - In Germany in recent years failures of more than 30-year-old prestressed concrete structures have been observed. In all these cases a quenched and tempered steel type, strength class St. 1420/1570 was used. In order to assess the corrosion risk, i.e. crack initiation and propagation, under depassivating conditions lifetime tests in environments relevant for building practice were carried out using different prestressing steels of this quenched and tempered type of material. From the results it can be concluded that the specific susceptibility of certain prestressing steels is the determining factor with respect to the occurrence of cracks rather than environmental factors. Translated Abstract Untersuchungen zum wasserstoffinduzierten Sprödbruch vergüteter Spannstähle In den letzten Jahren ist es verschiedentlich zu Schadensfällen von Spannbetonbauteilen gekommen, bei denen vergüteter Spannstahl der Festigkeitsklasse St 1420/1570 eingesetzt war. Durch systematische Untersuchungen an verschiedenen Typen dieser Stahlsorte sollte geklärt werden, ob unter depassivierenden Bedingungen Rißeinleitung und -ausbreitung unter praxisnahen Verhältnissen zu erwarten ist. Die durchgeführten Untersuchungen lassen folgern, daß die spezifische Anfälligkeit des Spannstahls für das Auftreten von Rissen einen wesentlich höheren Einfluß besitzt als die elektrolytseitigen Parameter, da sich die verschiedenen Stähle auch bei vergleichbaren Korrosionsangriffen unterschiedlich verhalten. KW - Prestressing steels KW - Corrosion PY - 2000 DO - https://doi.org/10.1002/(SICI)1521-4176(200002)51:2<80::AID-MACO80>3.0.CO;2-A SN - 0947-5117 SN - 1521-4176 N1 - Sprachen: Deutsch/Englisch - Languages: German/English VL - 51 IS - 2 SP - 80 EP - 90 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-807 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mietz, Jürgen A1 - Fischer, Joachim A1 - Isecke, Bernd T1 - Spannungsrißkorrosion an Spannstählen N2 - Im Rahmen einer Bauwerksuntersuchung an einer in nachträglicher Verbundbauweise hergestellten Brücke wurden Anrisse an Spannstählen der Quervorspannung festgestellt, ohne daß Verpreßmängel oder korrosionsfördernde Substanzen vorlagen. Bei dem verwendeten Werkstoff handelt es sich um einen in der ehemaligen DDR hergestellten vergüteten Stahl der Festigkeitsklasse St 140/160. Ursache für die Anrisse ist die in Laborversuchen nachgewiesene Empfindlichkeit dieses Stahles gegenüber wasserstoffinduzierter Spannungsrißkorrosion, die unter ungünstigen Bedingungen dazu führen kann, daß Vorschädigungen vor dem Verpressen eintreten. Zusätzlich durchgeführte Magnetpulverprüfungen an ausgewählten Bereichen der Längsvorspannung ergaben keinerlei Hinweise auf Anrisse. Translated Abstract Stress corrosion cracking of prestressing steels During the investigation of a post-tensioned bridge structure incipient cracks of the prestressing steels of the transverse prestressed members were observed. Defects related to non-injected ducts or the presence of corrosion inducing substances could not be detected. The prestressing steel used is a quenched and tempered steel, strength class St 140/160, which was produced in the former GDR. The cause for the cracks is the susceptibility of this type of steel to hydrogen-induced stress corrosion cracking as could be shown in laboratory tests. Under unfavourable conditions cracks can be initiated before grouting. Additional magnetic particle tests at selected areas of the longitudinal prestressed members did not indicate any signs for incipient cracks. KW - Corrosion PY - 1999 SN - 0947-5117 SN - 1521-4176 VL - 50 IS - 9 SP - 535 EP - 540 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-831 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Taffe, Alexander A1 - Schaurich, Dieter A1 - Weritz, Friederike A1 - Wilsch, Gerd T1 - Laser-Induced Breakdown Spectroscopy (Libs) in Civil Engineering T2 - 9th European Conference on NDT : ECNDT Berlin 2006 CY - Berlin, Germany DA - 2006-09-25 KW - NDT-EC KW - LIBS KW - Spectroscopy KW - Concrete damages KW - Chloride KW - Sulphate KW - Corrosion KW - Condition assessment KW - Quality assurance PY - 2006 SN - 3-931381-86-2 SP - 1(?) EP - 6(?) PB - European Federation for Non-Destructive Testing CY - Berlin AN - OPUS4-13690 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mietz, Jürgen A1 - Burkert, Annette A1 - Burkert, Andreas A1 - Eich, Gerd T1 - Investigations on the protection effect of filling materials for post-tensioning systems under construction conditions N2 - About the long-term protection behaviour of corrosion protection materials (filling materials) for prestressed systems under critical environmental conditions is only little known. The corrosion protection effect is usually based on theoretical considerations and is proven by short-term tests. The selection of the different products is mainly made according to economical or workability criteria. In a research project the barrier effect of different commercial corrosion protection materials (waxes as well as oil-based greases) against water, their tendency for undercutting as well as their additional corrosion protection effect were investigated. The exposure tests were carried out with non-stressed as well as stressed prestressing steel specimens which were subjected to critical conditions (condensed water, artificial soil solution, direct soil contact). Parallel to these long-term exposure tests the applicability of different electrochemical techniques and their significance with respect to testing the corrosion protection ability and water absorption was evaluated. Within the project a suitable method for simple testing the performance of corrosion protection materials under real conditions was developed. By means of a small compact cell submicroscopical reactions of the used sensors could be measured. The high sensitivity of this measuring technique enables the detection of degradation processes at thin protection layers. KW - Prestressed systems KW - Corrosion KW - Corrosion protection KW - Electrochemical tests KW - Grease KW - Wax PY - 2006 DO - https://doi.org/10.1002/maco.200603986 SN - 0947-5117 SN - 1521-4176 VL - 57 IS - 11 SP - 843 EP - 851 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-13931 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pfennig, A. A1 - Zastrow, Philip A1 - Kranzmann, Axel T1 - Influence of heat treatment on the corrosion behaviour of stainless steels during CO2-sequestration into saline aquifer N2 - The appropriate strength of steels used for saline aquifer carbon capture and storage sites (CCS) is usually achieved by applying heat treatments. Thus, heat treatment influences the corrosion resistance for injection pipe steels with 13% chromium and different carbon content: 1.4034/X46Cr13 and 1.4021/X20Cr13 in CO2 saturated saline aquifer water at 60 °C, 1 and 100 bar. X46Cr13 shows better corrosion resistance with respect to corrosion rate, number of pits and maximum intrusion depth. Low corrosion rates are obtained for steels with martensitic microstructures exposed to supercritical CO2 at 100 bar, whereas normalized steels show better corrosion resistance at ambient pressure. KW - Steel KW - Heat treatment KW - CO2 injection KW - Carbon capture and storage (CCS) KW - Corrosion PY - 2013 DO - https://doi.org/10.1016/j.ijggc.2013.02.016 SN - 1750-5836 VL - 15 SP - 213 EP - 224 PB - Elsevier Ltd. CY - New York, NY [u.a.] AN - OPUS4-27994 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ruhl, Aki Sebastian A1 - Kranzmann, Axel T1 - Corrosion in supercritical CO2 by diffusion of flue gas acids and water N2 - Carbon capture and storage (CCS) includes processing of supercritical carbon dioxide (scCO2). The carbon dioxide (CO2) stemming from flue gases contains acid forming impurities, especially in the case of coal fired power plants. In the present work, the mobility and reactivity of acids in supercritical scCO2 was investigated. The corrosive attack of low alloyed carbon steel (material 1.0484) by water (H2O) alone in scCO2 was negligible. Nitric acid (HNO3) was very mobile and corrosive towards the carbon steel while sulfuric acid did not migrate through the scCO2 to react with the steel surface. Hydrochloric acid in scCO2 was very mobile and reactive towards both carbon steel and high alloyed test equipment. Gravimetric analyses revealed a severe material loss after corrosion in the presence of HNO3. Thickness measurements showed localized material losses. KW - Supercritical CO2 KW - Corrosion KW - Carbon steel KW - Carbon capture and storage KW - CCS KW - Flue gas acids PY - 2012 DO - https://doi.org/10.1016/j.supflu.2012.04.015 SN - 0896-8446 VL - 68 SP - 81 EP - 86 PB - Elsevier CY - New York, NY [u.a.] AN - OPUS4-28054 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Quiroz Penaranda, Vanessa A1 - Gumenyuk, Andrey A1 - Rethmeier, Michael T1 - Comparison between CO2- and Nd: YAG-laser beam welding of high-strength CrMnNi steels for the automotive industry N2 - IIW-2326 Austenitic and austenitic-ferritic CrMnNi-stainless steels are suitable materials in the transport and automotive industry due to their high corrosion resistance and high strength that allows weight and cost savings. This study focuses on the laser weldability of a commercial lean duplex and an austenitic high manganese stainless steel. The impact of different laser sources, i.e. a 5 kW CO2- and a 4 kW Nd:YAG-laser, and of the main process parameters on the resulting weld quality will be investigated. One important aspect will concern the appearance of weld defects such as pores and hot cracks. The factors causing such internal imperfections will be analysed in order to find effective methods for preventing them. Weld microstructure and the associated corrosion and mechanical properties will be assessed with different techniques and adequate process parameters for high quality welds will be determined. The advantages and limitations of the applied welding processes will be evaluated for future applications. KW - Laser beam welding KW - Stainless steel KW - Austenitic KW - Duplex KW - Weld microstructure KW - Pores KW - Cracks KW - Corrosion KW - Tensile strength PY - 2012 SN - 0043-2288 SN - 1878-6669 VL - 56 IS - 11/12 SP - 129 EP - 142 PB - Springer CY - Oxford AN - OPUS4-27911 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pfennig, Anja A1 - Schulz, S. A1 - Werlitz, T. A1 - Bülow, E. A1 - Wetzlich, S. A1 - Tietböhl, J. A1 - Frieslich, C. A1 - Kranzmann, Axel T1 - Influence of heat treatment on the corrosion of steels in CCS environment T2 - TMS 2012 - 141st Annual Meeting & Exhibition CY - Orlando, FL, USA DA - 2012-03-11 KW - CCS KW - Carbon capture and storage KW - Corrosion KW - Steel KW - Pipeline KW - Carbon KW - Heat treatment KW - CO2-storage PY - 2012 SN - 978-1-11829-607-3 VL - 1 IS - Supplemental Proceedings SP - 103 EP - 110 PB - John Wiley & Sons CY - Hoboken, NJ, USA AN - OPUS4-28007 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weber, Gert A1 - Thommes, H. A1 - Gaul, H. A1 - Hahn, O. A1 - Rethmeier, Michael T1 - Mechanical properties of weldbonded joints of advanced high strength steels N2 - In lightweight car body shell mass production, due to requirements on vehicle weight reduction and carbon dioxide emissions, joining of advanced high strength steels (AHSS) with different joining procedures and especially hybrid bonding techniques is becoming more and more important. One of these hybrid bonding techniques is the combination of resistance spot welding and adhesive bonding called weldbonding. One of the important advantages of weldbonded joints in comparison to resistance spot welded joints are the enhanced mechanical properties. To guarantee sufficiently high quality conditions regarding the strength of the weldbonded joints, the influences of the applied adhesive systems and of different base metal combinations are studied. This is carried out for both non-corrosive and corrosive environments and for the choice of different joining parameters settings. In particular, the mechanical behaviour of the weldbonded joints is investigated under quasi-static, impact and fatigue loads. Furthermore, the energy absorption of the weldbonded joints for both non-corrosive and corrosive environments is studied. It is shown that the weldbonded joints possess higher mechanical strengths in all load cases (quasi-static, impact and fatigue). Corrosive attack affects weldbonded joints, and the quasi-static strength is reduced. Resistance spot welded joints are not affected by the corrosive attack, but even after several weeks of corrosive attack, the quasi-static strength of weldbonded joints remains higher than that of resistance spot welded joints. KW - Weldbonded joints KW - Corrosion KW - Mechanical strength KW - Fracture behaviour KW - Fatigue KW - Crash behaviour PY - 2011 DO - https://doi.org/10.1163/016942411X580090 SN - 0169-4243 SN - 1568-5616 VL - 25 IS - 18 SP - 2369 EP - 2389 PB - VNU Science Press CY - Utrecht AN - OPUS4-24513 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - 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 - Dantan, Nathalie A1 - Höhse, Marek A1 - Karasyov, A.A. A1 - Wolfbeis, Otto S. T1 - Entwicklung eines optischen pH-Sensors zur Früherkennung korrosionsgefährdender Zustände in Stahlbeton KW - Korrosion KW - Stahlbeton KW - Monitoring KW - pH-Wert KW - Faseroptik KW - Sensorik KW - Corrosion KW - Steel-reinforced concrete KW - pH value KW - Fiber optic sensor PY - 2007 SN - 0340-837X SN - 0178-2312 SN - 0171-8096 VL - 74 IS - 4 SP - 211 EP - 216 PB - Oldenbourg CY - München AN - OPUS4-14971 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pettersson, C.O. A1 - Böllinghaus, Thomas A1 - Kannengießer, Thomas T1 - Corrosion testing of welds, a review of methods KW - Austenitic stainless steels KW - Carbon steels KW - Corrosion KW - Corrosion tests KW - Crevice corrosion KW - Duplex stainless steels KW - Fatigue strength KW - Galvanic corrosion KW - Intergranular corrosion KW - Low alloy steels KW - Mechanical properties KW - Nickel alloys KW - Pitting corrosion KW - Stress corrosion KW - Stainless steels KW - Steels KW - Unalloyed steels KW - Welded joints KW - Weld metal PY - 2007 SN - 0043-2288 SN - 1878-6669 VL - 51 IS - 7/8 SP - 79 EP - 106 PB - Springer CY - Oxford AN - OPUS4-15727 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN ED - Raupach, M. ED - Elsener, B. ED - Polder, R. ED - Mietz, Jürgen ED - M. Raupach, ED - Elsener, B. ED - R. Polder, ED - J. Mietz, T1 - Corrosion of reinforcement in concrete KW - Concrete KW - Corrosion KW - Reinforcement KW - Rehabilitation KW - Monitoring KW - Inhibitors PY - 2007 SN - 978-1-84569-210-0 SP - 1 EP - 312 PB - Woodhead Publishing Ltd CY - Cambridge, Great Britain AN - OPUS4-16588 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Moraes, Flavia A1 - Müller, Wolfgang A1 - Frischat, G.H. A1 - Müller, Ralf T1 - Corrosion and crystallization at the inner surfaces of glass bricks N2 - Glass bricks are important transparent building materials. They are produced by joining two halves of glass pressings at 600–700 °C. During this production process alkali oxides evaporate and are redeposited at the cooler inner front surfaces of the bricks. This surface layer reacts with H2O and CO2 from the residual brick atmosphere, leading to the formation of an alkali-rich silicate-hydrate layer of ≥50 nm thickness, which could be evidenced leading to a reduced nano-hardness of similar thickness, and from which NaHCO3 crystals can finally grow. Climate chamber experiments (repeated cooling between at -8 and -14 °C and reheating to 0 to 15 °C) resulted in reversible NaHCO3 crystallization and redissolution, presumably influenced by water evaporation or condensation and driven by the NaHCO3 supersaturation of the silicate-hydrate layer. Depending on the time–temperature schedule, different crystal morphologies became visible in this closed system, e.g. isolated spherical crystals, crystals arranged in chains and in double-chains, respectively, which can limit already the transmittance of the glass bricks. When a crack occurs or the brick is opened, the hygroscopic NaHCO3 crystals take up more H2O from the ambient, react irreversibly with the glass surface, finally leading to a total loss of transmittance. KW - Chemical properties KW - Chemical durability KW - Corrosion KW - Crystallization KW - Crystal growth KW - Nucleation KW - Glasses KW - Mass spectroscopy KW - Mechanical properties KW - Hardness KW - Indentation KW - Microindentation KW - Microscopy KW - Optical microscopy KW - Scanning electron microscopy KW - Optical properties KW - Optical spectroscopy KW - Oxide glasses KW - Alkali silicates KW - Soda-lime-silica KW - Surfaces and interfaces PY - 2008 DO - https://doi.org/10.1016/j.jnoncrysol.2007.07.086 SN - 0022-3093 VL - 354 IS - 2-9 SP - 284 EP - 289 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-16433 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eichler, Thorsten A1 - Burkert, Andreas A1 - Beck, Matthias T1 - Electrochemical noise measurements on unalloyed steel in chloride-containing alkaline environment N2 - The investigations discussed in this paper aim to clarify whether electrochemical noise measurements (ENM) are capable for application in concrete and mortar, particularly with regard to pitting initiation in such environment. For these purposes, the results of several different test series are compared and discussed. Based on investigations on passivity and pitting corrosion in alkaline solutions with different chloride contents further results in cement paste, mortar and concrete are evaluated. KW - Electrochemical noise KW - Corrosion KW - Steel in Concrete KW - Chlorides KW - Pitting Corrosion KW - Cement KW - Mortar KW - Black Steel PY - 2007 DO - https://doi.org/10.1002/maco.200704089 SN - 0947-5117 SN - 1521-4176 VL - 58 IS - 12 SP - 961 EP - 969 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-16374 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Pfennig, Anja A1 - Kranzmann, Axel ED - Roland Span, ED - Ingo Weber, T1 - Effect of CO2 on the stability of steels with 1% and 13% Cr in saline water T2 - 15th International Conference on the Properties of Water and Steam (ICPWS XV), "Water, Steam, and Aqueous Solutions - Advances in Science and Technology for Power Generation" CY - Berlin, Germany DA - 2008-09-07 KW - Steel KW - Corrosion KW - Injection tube KW - Carbonate scale KW - CO2-storage KW - CO2-injection PY - 2008 SN - 978-3-931384-64-7 IS - Session 06: Electro-12 SP - 1 EP - 11 AN - OPUS4-17869 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Dantan, Nathalie A1 - Habel, Wolfgang A1 - Wolfbeis, Otto S. ED - Udd, E. T1 - Fiber optic pH sensor for early detection of danger of corrosion in steel-reinforced concrete structures T2 - 12th SPIE International Symposium "Smart Structures and Materials 2005 CY - San Diego, CA, USA DA - 2005-05-06 KW - Korrosion KW - Stahlbeton KW - Monitoring KW - pH KW - Faseroptischer Sensor KW - Langzeitstabilität KW - Indikator KW - Immobilisierung KW - Corrosion KW - Steel-reinforced concrete KW - Fiber optic sensor KW - Long-term stability KW - Indicator KW - Immobilization PY - 2005 SN - 0-8194-5739-6 SN - 1605-7422 N1 - Serientitel: SPIE proceedings series – Series title: SPIE proceedings series IS - 5758 SP - 274 EP - 284 PB - SPIE CY - Bellingham AN - OPUS4-11768 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rosemann, P. A1 - Müller, Thoralf A1 - Babutzka, Martin A1 - Heyn, Andreas ED - J. Grosch, ED - E.J. Mittemeijer, T1 - Qualitätsbewertung von Schneidwaren durch Kurzzeit-Korrosionsprüfung N2 - Bei der Qualitätsbewertung von Schneidwaren aus nichtrostenden martensitischen Chrom-Stählen stellt die Überprüfung der Korrosionsbeständigkeit ein wichtiges Kriterium dar. Allgemein üblich sind Wechseltauchversuche mit relativ hohem zeitlichem und auswertungsbedingtem Aufwand, die noch dazu zerstörend sind und teilweise fragwürdige Ergebnisse liefern. In den letzten Jahren wurden neue Ansatze der Prüfung geschaffen, die eine nahezu zerstörungsfreie Kurzzeit-Korrosionsprüfung erlauben. Es wird gezeigt, dass mit dem elektrochemischen Rauschen sehr empfindlich Einflüsse des Härtens und der Oberflächenbehandlung auf die Korrosionsbeständigkeit nachgewiesen werden können, wodurch eine schnelle und objektive Qualitätsbewertung innerhalb des Fertigungsprozesses und der Endkontrolle von Produkten möglich ist. Das für die Prüfmethodik ausgenutzte Phänomen des elektrochemischen Rauschens zielt darauf ab, den Beginn der Korrosion empfindlich und schnell zu detektieren, ohne die Prüfbedingungen maßlos zu verschärfen und Produkte damit zu zerstören. Neben der Funktionalität der Prüfung stehen aber auch die Anwenderfreundlichkeit und somit die Akzeptanz bei den Herstellern im Vordergrund. Aus diesem Grund wurde zusätzlich ein Indikatortest (KorroPad) als praxistaugliche Alternative zum elektrochemischen Rauschen angewendet. Die Ergebnisse zeigen eine gute Übereinstimmung beider Methoden und ermöglichen eine effektive betriebliche Qualitätsüberwachung von Schneidwaren. KW - Schneidwaren KW - Nichtrostender Stahl KW - Korrosion KW - Prüfmethoden KW - Qualitätskontrolle KW - Cutlery KW - Stainless steel KW - Corrosion KW - Testing methods KW - Quality control PY - 2013 DO - https://doi.org/10.3139/105.110195 SN - 1867-2493 VL - 68 IS - 5 SP - 224 EP - 235 PB - Hanser CY - München AN - OPUS4-29341 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pfennig, Anja A1 - Wolf, Marcus A1 - Wiegand, Reiner A1 - Kranzmann, Axel A1 - Bork, Claus-Peter T1 - Corrosion fatigue behavior and S-N-curve of X46Cr13 exposed to CCS-environment obtained from laboratory in-situ-experiments N2 - In corrosive environments such as CCS bore holes or geothermal power plants the materials loaded cyclically are also exposed constantly to the highly corrosive hot thermal water. The lifetime reduction of (X46Cr13, AISI 420C) is demonstrated in in-situ-laboratory experiments (T=60 °C, geothermal brine: Stuttgart Aquifer flow rate: 9 Nl/h, CO2). S-N plots, micrographic-, phase-, fractographic- and surface analysis were applied to obtain sustainable information on the corrosion fatigue behavior. Maximum number of cycles (here 12.5 x 106 cycles to failure) is reached at σa =173 MPa. No typical fatigue strength exists and passive corrosion fatigue is most likely failure cause. KW - Steel KW - Supercritical CO2 KW - Pipeline KW - Corrosion KW - CCS KW - CO2-storage PY - 2013 DO - https://doi.org/10.1016/j.egypro.2013.06.499 SN - 1876-6102 VL - 37 SP - 5764 EP - 5772 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-29342 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Bender, S. A1 - Göllner, J. A1 - Heyn, Andreas A1 - Blawert, C. A1 - Srinivasan, P.B. ED - Pekguleryuz, M.O. ED - Kainer, K.U. ED - Kaya, A. T1 - Corrosion and surface finishing of magnesium and its alloys N2 - While the possibilities of improving corrosion resistance (especially galvanic corrosion) by alloying are limited, surface finishing of magnesium alloys is the alternative for improving corrosion resistance. Due to the low corrosion potential of Mg and the danger of galvanic corrosion in the case of a coating defect, the choice of coatings is limited. This chapter will summarize the corrosion behavior of magnesium alloys and the metallurgical possibilities to improve the corrosion resistance of the alloys and reviewing critically the most commonly used surface treatments and coatings for magnesium. KW - Corrosion KW - Corrosion testing KW - Negative difference effect (NDE) KW - Conversion coatings KW - Plasma electrolytic oxidation KW - Organic coatings KW - Galvanic coatings PY - 2013 SN - 978-0-85709-088-1 SN - 978-0-85709-729-3 DO - https://doi.org/10.1533/9780857097293.232 IS - Chapter 7 SP - 232 EP - 265 PB - Woodhead Publishing Ltd AN - OPUS4-29332 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bender, S. A1 - Holzhausen, U. A1 - Heyn, Andreas T1 - Investigations of the aqueous corrosion of pretreated magnesium alloys by means of electrochemical noise measurements N2 - An important possibility to improve the corrosion behaviour of magnesium alloys is the application of protective coatings. The quality of such coatings depends mainly on the pretreatment and the exposure conditions after pretreatment. Since magnesium surfaces change much faster under atmospheric conditions than those of almost any other technical material, it is necessary to pay special attention to this particular feature. The activity of acid-pickled surfaces of the magnesium alloys AZ31 and AZ91 in dependence on the exposure time and the humidity conditions was investigated with electrochemical noise (EN) measurements. In addition to pickling, plasma chemical vapour deposition processes open new possibilities for an economical, as well as ecologically quite safe, pretreatment. The results of EN investigations after acid pickling as well as specific plasma oxidation treatments of the two magnesium alloys after exposure to air with different humidities are presented. KW - Corrosion KW - CVD KW - Electrochemical noise KW - Magnesium alloys KW - Pretreatment PY - 2013 DO - https://doi.org/10.1002/maco.201206741 SN - 0947-5117 SN - 1521-4176 VL - 64 IS - 8 SP - 708 EP - 713 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-29073 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rosemann, P. A1 - Schmidt, J. A1 - Heyn, Andreas T1 - Short and long term degradation behaviour of Mg-1Ca magnesium alloys and protective coatings based on plasma-chemical oxidation and biodegradable polymer coating in synthetic body fluid N2 - The main problem limiting the application of magnesium alloys as biodegradable implant material is its high degradation rate. In order to slow down the corrosion rate an extrusion process and specific coating systems based on plasma-chemical oxidation (PCO) and organic dip coating with poly(ʟ-lactid-co-caprolacton) (PLLC) were applied on Mg–1Ca magnesium alloy. The additional PLLC coating is used to delay the start of substrate corrosion, while the purpose of the PCO coating is to decrease the substrate corrosion rate. The corrosion behaviour was investigated in synthetic body fluid (SBF) through measurement of the hydrogen evolution rate in long term tests and polarisation and electrochemical noise measurements in short term tests. The results showed significant differences between the cast and extruded alloys and a decrease of the corrosion rate due to corrosion product formation. The combination of both coating systems resulted in a significant delay of metal substrate corrosion and all coating systems showed good correlation between short and long term tests. The combination of the three investigation methods provides the possibility to gain more information about the degradation behaviour and break down of protective coatings. KW - Coatings KW - Corrosion KW - Electrochemical noise KW - Magnesium KW - Plasma-chemical oxidation PY - 2013 DO - https://doi.org/10.1002/maco.201206590 SN - 0947-5117 SN - 1521-4176 VL - 64 IS - 8 SP - 714 EP - 722 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-29074 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 - GEN A1 - Pfennig, Anja A1 - Kranzmann, Axel ED - C.A. Brebbia, ED - V. Popov, T1 - Influence of CO2 on the corrosion behaviour of 13Cr martensitic stainless steel AISI 420 and low-alloyed steel AISI 4140 exposed to saline aquifer water environment T2 - 17th International Conference on Modelling, Monitoring and Management of Air Pollution CY - Tallinn, Estonia DA - 2009-07-20 KW - Steel KW - Pipeline KW - Corrosion KW - CCS KW - Carbon capture KW - CO2-injection PY - 2009 SN - 978-1-84564-195-5 DO - https://doi.org/10.2495/AIR090371 SN - 1746-448X SN - 1746-3541 VL - 123 SP - 409 EP - 418 PB - WIT Press AN - OPUS4-19783 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Pfennig, A. A1 - Linke, B. A1 - Kranzmann, Axel T1 - Predicting the long term corrosion behaviour of pipe steels used at the CCS-site Ketzing, Germany in laboratory CO2-saturated saline aquifer CCS-environment T2 - First international conference on materials for energy CY - Karlsruhe, Germany DA - 2010-07-04 KW - CCS KW - Corrosion KW - Steels KW - Injection pipe PY - 2010 SN - 978-3-89746-117-8 IS - Paper 1067 SP - 1005 EP - 1007 AN - OPUS4-21684 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Pfennig, Anja A1 - Linke, Barbara A1 - Kranzmann, Axel T1 - Carbon capture and storage technique (CCS): Reliability of pipe steels used in Ketzin, Germany verified in laboratory saline aquifer corrosion experiments N2 - During the compression emission gasses in deep geological layers (Carbon Capture and Storage, CCS) CO2-corrosion will become a relevant safety issue. The reliability of the steels used at the geological onshore CCS-site at Ketzin, Germany, (heat treated steel 42CrMo4 (1.7225, AISI 4140) used for casing, and the martensitic stainless injection pipe steels X46Cr13 (1.4034, AISI 420 C), X20Cr13 (1.4021, AISI 420 J), X35CrMo17 (1.4122)) is demonstrated in 1 and 2 years laboratory experiments. Samples were kept in a synthetic aquifer environment similar to the geological CCS-site at Ketzin, Germany 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, after a series of heat treatments (700 h to 2 years). Due to very slow mass loss at extended exposure times to CCS-environment one year is sufficient to predict stable surface corrosion rates from laboratory experiments. The non-linear isothermal surface corrosion behaviour of the steels reveals surface corrosion rates around 0.1 to 0.8 mm/year, when obtained by mass gain. The loss of the base material is higher when calculated from the corrosion layer magnitude due to the unpredictable local corrosion attacks. Severe pit corrosion (pit heights ca. 4.5 mm) are only located on the high chromium 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. T2 - MWWD & IEMES 2010 - 6th International conference on marine waste water discharges and coastal environment CY - Langkawi, Malaysia DA - 2010-10-25 KW - Saline aquiver KW - Environmental issues KW - CCS KW - CO2-injection KW - CO2-storage KW - Corrosion KW - Phase formation PY - 2010 SN - 978-9944-5566-4-4 IS - Paper 047_P SP - 1 EP - 17 AN - OPUS4-22333 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Quiroz Penaranda, Vanessa A1 - Gumenyuk, Andrey A1 - Rethmeier, Michael T1 - Laser beam weldability of high-manganese austenitic and duplex stainless steel sheets N2 - Manganese alloyed stainless steels represent a cost-effective alternative to conventional CrNi- stainless steels due to strong fluctuations of the market prices for nickel seen during the last years. In CrMnNi steels, nickel is partially replaced by lower-cost manganese and small amounts of nitrogen for stabilization of the austenitic phase. This also brings benefits regarding the mechanical properties, as it results in an increased material strength. Laser beam welding of such materials was investigated for direct comparison with standard CrNi steels. Main emphasis was laid on finding adequate process parameters to achieve a stable welding process and obtain a good weld quality. Two different laser sources, a 4.4 kW Nd:YAG and a 5 kW CO2 laser, were used to weld 1.5 mm stainless steel sheets in continuous wave mode. A high-Mn austenitic (1.4376) and a lean duplex (1.4162) steel, as well as the standard austenitic (1.4301) and duplex (1.4362) grades were selected as test materials. Both butt and lap joint configurations were studied. Experiments were carried out systematically, varying the welding speed, laser power and focal point position in order to determine adequate process windows. The influence of the shielding gas type and flow rate on the process stability and the weld quality were investigated. The effects of weld edge preparation on the weld appearance and quality levels attained were also examined. The obtained welded joints were subjected to radiographic tests for detection of internal imperfections. Also a metallurgical characterization of the samples regarding the resulting phase composition or balance and hardness depending on the welding process parameters was conducted. Furthermore, tensile and potentiodynamic tests were performed to evaluate the mechanical and corrosion properties, respectively. The results provide an insight into the advantages and limitations of the laser beam welding process for joining high-manganese alloyed stainless steels. Conditions for the production of defect-free and corrosion-resistant welds having good mechanical properties could be determined. KW - Austenitic stainless steels KW - Corrosion KW - CO2 lasers KW - Duplex stainless steels KW - Laser welding KW - Manganese KW - Mechanical properties KW - Shielding gases KW - YAG lasers KW - Weldability PY - 2012 SN - 0043-2288 SN - 1878-6669 VL - 56 IS - 1/2 SP - 9 EP - 20 PB - Springer CY - Oxford AN - OPUS4-25404 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hong, Shuxian A1 - Lai Wai-Lok, Wallace A1 - Helmerich, Rosemarie T1 - Monitoring accelerated corrosion in chloride contaminated concrete with ground penetrating radar T2 - 14th International conference on ground penetrating radar - GPR 2012 CY - Shanghai, China DA - 2012-06-04 KW - GPR KW - Reinforcing steel KW - Corrosion KW - Chloride PY - 2012 SN - 978-1-4673-2663-6 SP - 1 EP - 6(?) AN - OPUS4-26122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichler, Thorsten A1 - Isecke, Bernd A1 - Wilsch, Gerd ED - Forde, M.C. T1 - Investigations on the secondary protection mechanisms in cathodic protection applications N2 - A joint research project was accomplished by ibac and BAM with the aim to develop a numerical model of cathodic protection (CP) of reinforced concrete with a special focus on CP of the rear reinforcement layer. The model was intended to include the effects of chemical alterations within the concrete and the steel concrete interface, which are induced by long-term application of CP. The investigations presented in this paper focus on the migration of chloride ions due to small electric fields as applied during cathodic protection of steel in reinforced concrete structures and its impact on polarisation characteristics. A comparatively new method, laser induced breakdown spectroscopy (LIBS), was used to determine chloride profiles on laboratory specimens in order to investigate one of several model parameters to describe cathodic protection of the rear reinforcement of reinforced concrete structures. These investigations are described elsewhere, [1]. The paper focuses on long term polarisation tests and their impact on the charge depending cathodic polarisation behaviour of laboratory specimens. T2 - Structural faults & repair 2012 - 14th International conference and exhibition CY - Edinburgh, Scotland DA - 2012-07-03 KW - Concrete KW - Cathodic protection KW - Chloride migration KW - Corrosion KW - Steel in concrete PY - 2012 SN - 0-947664-71-7 SP - 1 EP - 6 PB - Engineering Technics Press AN - OPUS4-26413 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Broomfield, J. A1 - Fischer, Joachim A1 - Mietz, Jürgen A1 - Schneck, U. T1 - Case studies N2 - In this paper, some quite different survey tasks are described, and it can be seen that corrosion surveys will follow a certain scheme of data acquisition (first NDT measurements, than detailed testing on suspect areas), but the individual scope of on-site measurements may have a vast variety according to the local circumstances, and the interpretation always has to refer to a wider set of information than the data readings only. KW - Corrosion surveys KW - Non-destructive testing KW - Reinforcement KW - Concrete KW - Potential mapping KW - Corrosion PY - 2013 DO - https://doi.org/10.1002/maco.201206649 SN - 0947-5117 SN - 1521-4176 VL - 64 IS - 2 SP - 147 EP - 160 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-29730 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zerbst, Uwe A1 - Klinger, Christian A1 - Klingbeil, Dietmar T1 - Structural assessment of railway axles - A critical review N2 - The safety assessment of railway axles is based on a two-stage approach: fatigue strength design and regular inspections which, in terms of a general safety philosophy refer to safe-life and damage tolerance concepts. Starting with a recent failure case, a broken axle of a German high speed train, a discussion is presented on issues of both safety levels. These include ideas for finite life design, the treatment of in-service effects on the fatigue strength due to flying ballast damage and corrosion pits, the effect of corrosion on fatigue crack initiation and propagation, potential effects of non-metallic inclusions in steels, the way to detect them by quality control measures and reliability aspects of non-destructive testing with respect to the detection of fatigue cracks. Proposals are made how the safety level could be further improved. KW - Railway axles KW - Safe life design KW - Damage tolerance design KW - Non-destructive testing KW - Flying ballast impact KW - Corrosion KW - Non-metallic inclusions PY - 2013 UR - http://www.sciencedirect.com/science/article/pii/S1350630712002531 SN - 1350-6307 SN - 1873-1961 VL - 35 IS - Special issue on ICEFA V- Part 1 SP - 54 EP - 65 PB - Elsevier Science Publ. CY - Oxford AN - OPUS4-29715 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmigalla, S. A1 - Bender, S. A1 - Heyn, Andreas A1 - Schmidt, J. A1 - Hort, N. T1 - Investigation of biodegradation behaviour of an Mg-1Ca alloy influenced by heat treatment and applying plasma-chemical oxidation layers N2 - The degradation behaviour of an Mg-1Ca alloy is investigated in vitro to figure out the possibilities of influencing the degradation behaviour of such an alloy by applying heat treatment as well as the use of a coating system based on plasma-chemical oxidation. It is shown that an optimised solution annealing (T4-heat treatment) can reduce the degradation rate while an additional ageing between 240 and 300 °C (T6-heat treatment) increases it. A coating generated by plasma-chemical oxidation reduces the degradation rate in the immersion test. Its effect is depending on the former heat treatment of the Mg-1Ca alloy as well as on the parameter during plasma-chemical oxidation. KW - Biodegradation KW - Magnesium alloys KW - Plasma-chemical oxidation KW - Magnesium KW - Thermal treatment KW - Corrosion KW - Electrochemistry PY - 2013 DO - https://doi.org/10.1002/maco.201106433 SN - 0947-5117 SN - 1521-4176 VL - 64 IS - 7 SP - 578 EP - 584 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-28933 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ebell, Gino A1 - Achenbach, R. A1 - Angst, U. A1 - Brem, M. A1 - Dauberschmidt, C. A1 - Eichler, T. A1 - Hariri, K. A1 - Harnisch, J. A1 - Keßler, S. A1 - Mayer, T.F. A1 - Mietz, Jürgen A1 - Pruckner, F. T1 - Merkblatt B 03 - Elektrochmische Potentialmessung zur Detektion von Bewehrungsstahlkorrosion N2 - Die Potentialmessung kann zum Auffinden korrosionsaktiver Bereiche neben Stahlbetonbauwerken auch bei Spannbetonbauwerken angewandt werden, die mit Spannstählen im direkten Verbund hergestellt werden. Bei Vorspannsystemen mit metallischen Hüllrohren im nachträglichen Verbund ist eine Aussage über den Korrosionszustand des Hüllrohrs, nicht aber des Spannstahls möglich. Messungen an Spannbetonbauteilen erfordern grundsätzlich die besonderen Kenntnisse eines Spezialisten. KW - Korrosion KW - Potentialfeldmessung KW - Corrosion KW - Concrete PY - 2021 SN - 978-3-947971-16-9 SP - 1 EP - 22 PB - DGZfP CY - Berlin AN - OPUS4-53091 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ebell, Gino A1 - Achenbach, R. A1 - Angst, U. A1 - Dauberschmidt, C. A1 - Eichler, T. A1 - Hariri, K. A1 - Harnisch, J. A1 - Keßler, S. A1 - Kosalla, M. A1 - Mayer, T.F. A1 - Mietz, Jürgen A1 - Pruckner, F. A1 - Sodeikat, C. T1 - Specification B 12 - Corrosion monitoring in reinforced and prestressed concrete structures N2 - This specification describes how corrosion monitoring is used to check the condition of reinforced and prestressed concrete members. In this specification, the term "corrosion monitoring" covers all methods in which it is possible to continuously track corrosion-relevant variables in the area of stationary, built-in sensors. This specification does not cover other possible methods, such as potential field measurements, involving the use of mobile, portable sensors that are placed temporarily on the membersurface to take measurements. KW - Korrosion KW - Corrosion KW - Monitoring PY - 2021 SN - 978-3-947971-14-5 SP - 1 EP - 55 PB - DGZfP CY - Berlin AN - OPUS4-53092 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pfennig, Anja A1 - Wolf, Marcus A1 - Kranzmann, Axel T1 - Corrosion and corrosion fatigue of steels in downhole CCS environment - A summary N2 - Static immersion tests of potential injection pipe steels 42CrMo4, X20Cr13, X46Cr13, X35CrMo4, and X5CrNiCuNb16-4 at T = 60 °C and ambient pressure, as well as p = 100 bar were performed for 700–8000 h in a CO₂-saturated synthetic aquifer environment similar to CCS sites in the Northern German Basin (NGB). Corrosion rates at 100 bar are generally lower than at ambient pressure. The main corrosion products are FeCO₃ and FeOOH with surface and local corrosion phenomena directly related to the alloy composition and microstructure. The appropriate heat treatment enhances corrosion resistance. The lifetime reduction of X46Cr13, X5CrNiCuNb16-4, and duplex stainless steel X2CrNiMoN22-5-3 in a CCS environment is demonstrated in the in situ corrosion fatigue CF experiments (axial push-pull and rotation bending load, 60 °C, brine: Stuttgart Aquifer and NGB, flowing CO₂: 30 L/h, +/- applied potential). Insulating the test setup is necessary to gain reliable data. S-N plots, micrographic-, phase-, fractographic-, and surface analysis prove that the life expectancy of X2CrNiMoN22-5-3 in the axial cyclic load to failure is clearly related to the surface finish, applied stress amplitude, and stress mode. The horizontal grain attack within corrosion pit cavities, multiple fatigue cracks, and preferable deterioration of austenitic phase mainly cause fatigue failure. The CF life range increases significantly when a protective potential is applied. KW - Steel KW - High alloyed steel KW - Corrosion KW - Corrosion fatigue KW - Carbon capture and storage PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-531391 DO - https://doi.org/10.3390/pr9040594 SN - 2227-9717 VL - 9 IS - 4 SP - 1 EP - 33 PB - MDPI CY - Basel AN - OPUS4-53139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steger, S. A1 - Horn, Wolfgang A1 - Eggert, G. A1 - Krekel, C. T1 - Are cellulose ethers safe for the conservation of artwork? New insights in their VOC activity by means of Oddy testing N2 - Cellulose ethers, like methyl cellulose (MC) or hydroxypropyl cellulose (HPC), are widely used in conservation. They also occur as additives and rheology modifiers in various products like dispersions or gels. Do such products release harmful volatile organic compounds (VOC) during their accelerated aging? A mass testing series utilizing the Oddy test of 60 commercial cellulose ethers ranks the products in safe for permanent use (P, no corrosion), only for temporary use (T, slight corrosion), and unsuitable at all (F, heavy corrosion). Results show that 55% of the products passed the test whereas 33% are for temporary use as slight corrosion occurred on at least one metal coupon and only 11% failed the Oddy test. Raman measurements of the corrosion products identified oxides like massicot, litharge, cuprite, and tenorite among carbonates (hydrocerussite, plumbonacrite), and acetates like basic lead acetate, lead acetate trihydrate as well as lead formate as main phases. For example, commercial, industrial Klucel® G (HPC) scored a T rating through slight corrosion on the lead coupon. Basic lead acetate among other phases indicates the presence of acetic acid. Additional measurements of the sample with thermal desorption GC–MS utilizing the BEMMA scheme confirm the high acetic acid outgassing and reveal the presence of a small amount of formaldehyde. KW - Cellulose ether KW - Corrosion KW - Oddy test KW - VOC KW - BEMMA PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547591 DO - https://doi.org/10.1186/s40494-022-00688-4 SN - 2050-7445 VL - 10 IS - 1 SP - 1 EP - 12 PB - Springer Open AN - OPUS4-54759 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ebell, Gino A1 - Mayer, T. F. A1 - Harnisch, J. A1 - Dauberschmidt, Ch. T1 - Corrosion monitoring of reinforced concrete structures:The DGZfP specification B12 Collaboration N2 - Corrosion monitoring of reinforced or prestressed concrete structures has becomeincreasingly important in recent years. Areas of application include componentsthat are no longer accessible after completion or where potential fieldmeasurements cannot be carried out due to existing coatings. Corrosion monitoringcan also be used to monitor the progress of corrosion in corroding systems, e.g. to prove the success of repair measures according to repair principle 8 in accordancewith EN 1504‐9 or repair method 8.3 in accordance with the DIBt repair guideline.It also could be used to prove the functionality of cathodic corrosion protectionsystems in accordance with ISO 12696. Despite the increasing importance ofcorrosion monitoring, no guidelines orrecommendations existed until 2018. Thisgap was closed by the English version of specification B12,“Corrosion Monitoringof Reinforced and Prestressed Concrete Structures,”of the German Society for Non‐Destructive Testing, which was published in 2021. This article introducesspecification B12 by explaining the basicmeasurement principles and illustratingthe potential of corrosion monitoring in new and existing buildings. KW - Corrosion KW - Monitoring PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580982 DO - https://doi.org/10.1002/maco.202313934 SN - 0947-5117 SP - 1 EP - 9 PB - Wiley VHC-Verlag AN - OPUS4-58098 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heyn, A. A1 - Meist, M. A1 - Michael, O. A1 - Babutzka, M. A1 - Valet, Svenja A1 - Ebell, Gino T1 - Electrochemical characterization of surfaces of galvanized steels under different exposure conditions using gel electrolytes N2 - The corrosion behavior of galvanized steels and zinc components under atmospheric exposure depends mostly on the corrosion product‐based cover layer formation under the prevailing conditions. The use of agar‐based gel electrolytes makes it possible to use electrochemical methods to obtain a characteristic value from these cover layers that describe their current and future protective capacity. It is shown here that different states of galvanized steel can be distinguished very well under laboratory conditions and that this method is also suitable for use under practical conditions. Based on the characteristic values and assuming future time of wetness, it is very easy to draw up a forecast for the future corrosion rate, which provides plausible values. KW - Materials Chemistry KW - Metals and Alloys KW - Surfaces, Coatings and Films KW - Mechanical Engineering KW - Mechanics of Materials KW - Environmental Chemistry KW - Corrosion KW - Znc PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599234 DO - https://doi.org/10.1002/maco.202414389 SP - 1 EP - 16 PB - Wiley VHC-Verlag AN - OPUS4-59923 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Valet, Svenja A1 - Bohlmann, Tatjana A1 - Burkert, Andreas A1 - Ebell, Gino T1 - Zinc acetate containing gel pads for electrochemical measurements of Zn samples N2 - Agar gel pads have been used for electrochemical measurements for some time. For zinc in particular, a standard method for measuring the stability of the corrosion product layer is being established. The main interpretation factor is the corrosion product layer resistance RL, as it is easy to determine and interpret. A high corrosion product layer resistance indicates a high level of protection. However, it is not yet known how low the corrosion product layer resistance is for freshly produced zinc samples. As zinc is highly active, it reacts immediately with the environment to form a corrosion product layer, which affects the corrosion product layer resistance. The addition of zinc acetate to the agar gel pads prevents the formation of a surface layer and destroys existing ones. This makes it possible to measure an almost corrosion product-free zinc surface. This is important in defining the range of corrosion product layer resistance for a protective surface. KW - Electrochemistry KW - General Chemical Engineering KW - Analytical Chemistry KW - Corrosion KW - Zinc KW - Korrosion PY - 2023 DO - https://doi.org/10.1016/j.jelechem.2023.117814 SN - 1572-6657 VL - 948 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-59079 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wetzel, Annica A1 - Morell, Daniel A1 - von der Au, Marcus A1 - Wittstock, Gunther A1 - Ozcan, Ozlem A1 - Witt, Julia T1 - Transpassive Metal Dissolution vs. Oxygen Evolution Reaction: Implication for Alloy Stability and Electrocatalysis T1 - Transpassive Metallauflösung vs. Sauerstoffentwicklung: Auswirkungen auf Legierungsstabilität und Elektrokatalyse N2 - Multi-principal element alloys (MPEAs) are gaining interest in corrosion and electrocatalysis research due to their electrochemical stability across a broad pH range and the design flexibility they offer. Using the equimolar CrCoNi alloy, we observe significant metal dissolution in a corrosive electrolyte (0.1 M NaCl, pH 2) concurrently with the oxygen evolution reaction (OER) in the transpassive region despite the absence of hysteresis in polarization curves or other obvious corrosion indicators. We present a characterization scheme to delineate the contribution of OER and alloy dissolution, using scanning electrochemical microscopy (SECM) for OER-onset detection, and quantitative chemical analysis with inductively coupled-mass spectrometry (ICP-MS) and ultraviolet visible light (UV-Vis) spectroscopy to elucidate metal dissolution processes. In-situ electrochemical atomic force microscopy (EC-AFM) revealed that the transpassive metal dissolution on CrCoNi is dominated by intergranular corrosion. These results have significant implications for the stability of MPEAs in corrosion systems, emphasizing the necessity of analytically determining metal ions released from MPEA electrodes into the electrolyte when evaluating Faradaic efficiencies of OER catalysts. The release of transition metal ions not only reduces the Faradaic efficiency of electrolyzers but may also cause poisoning and degradation of membranes in electrochemical reactors. N2 - Multi-Hauptelement-Legierungen (MPEAs) gewinnen in der Korrosions- und Elektrokatalyseforschung aufgrund ihrer elektrochemischen Stabilität über einen breiten pH-Bereich und der Vielfalt der möglichen chemischen Zusammensetzungen zunehmend an Interesse. In unseren Untersuchungen mit der äquimolaren CrCoNi-Legierung in einem sauren Elektrolyten (0.1 M NaCl, pH 2) beobachteten wir eine signifikante Metallauflösung, die mit der Sauerstoffentwicklungsreaktion (OER) im transpassiven Bereich einhergeht, obwohl in zyklischen Polarisationskurven keine Hysterese auftrat oder andere offensichtliche Korrosionsindikatoren vorlagen. In diesem Artikel wird ein Charakterisierungskonzept eingeführt, dass die Beiträge der OER und der Legierungsauflösung differenziert. Hierfür kommt die elektrochemische Rastermikroskopie (SECM) zum Nachweis des Beginns der OER und die quantitative chemische Analyse mit induktiv gekoppelter Massenspektrometrie (ICP-MS) und UV/Vis-Spektrometrie zur Aufklärung der Metallauflösungsprozesse zum Einsatz. Die elektrochemische In situ-Atomkraftmikroskopie (EC-AFM) zeigte, dass die intergranulare Korrosion der dominierende Mechanismus der transpassive Metallauflösung von CrCoNi ist. Diese Ergebnisse besitzen erhebliche Auswirkungen für die Beurteilung der Stabilität von MPEAs in Korrosionssystemen und der Stromausbeute von OER-Katalysatoren auf der Basis von MPEAs. Die Daten unterstreichen die Notwendigkeit der analytischen Bestimmung von Metallionen, die von MPEA-Elektroden freigesetzt werden. Die Freisetzung von Übergangsmetallionen verringert nicht nur die Stromausbeute von Elektrolyseuren, sondern kann zu einer Schädigung von Membranen in elektrochemischen Reaktoren führen. KW - Transpassive dissolution KW - Corrosion KW - Multi-prinicpal element alloys (MPEAs) KW - Passivation PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597045 DO - https://doi.org/10.1002/anie.202317058 SP - 1 EP - 8 PB - Wiley VHC-Verlag AN - OPUS4-59704 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 - JOUR A1 - Kauss, N. A1 - Rosemann, Paul A1 - Halle, T. T1 - Age-hardening behaviour, microstructure and corrosion resistance of the copper alloyed stainless steel 1.4542 N2 - The copper alloyed stainless steel 1.4542 (X5CrNiCuNb16-4) is used in different areas due to its good mechanical properties and corrosion resistance. Strength and corrosion 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 chromium carbides can reduce the corrosion resistance. Different ageing states were produced to investigate the precipitation behaviour with various methods. Furthermore, the influence of cold-rolling on the precipitation behaviour was studied in comparison to a solution annealed state without deformation. The microstructure was studied by SEM and the variations of hardness and magnetic proportion were characterised. The electrochemical potentiodynamic reactivation (EPR) was used to determine the corrosion resistance and detect chromium depletion in all heattreated states. The results show that a work hardening accelerates the precipitation rate, while ageing at 600 °C reduces the corrosion resistance due to chromium depletion. T2 - WTK2018 CY - Chemnitz DA - 14.03.2018 KW - Corrosion KW - Corrosion resistance KW - Corrosion testing KW - EPR KW - Heat treatment KW - Stainless steel PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-452482 DO - https://doi.org/10.1088/1757-899X/373/1/012020 SN - 1757-899X SN - 1757-8981 VL - 373 SP - Article 012020, 1 EP - 9 PB - Institute of Physics CY - London AN - OPUS4-45248 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR 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 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-457117 DO - https://doi.org/10.1088/1757-899X/373/1/012009 SN - 1757-8981 VL - 373 IS - 1 SP - 012009, 1 EP - 10 PB - IOP Publishing Ltd AN - OPUS4-45711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Balzer, M. A1 - Fenker, M. A1 - Kappl, H. A1 - Müller, Thoralf A1 - Heyn, A. A1 - Heiss, A. A1 - Richter, A. T1 - Corrosion protection of steel substrates by magnetron sputtered TiMgN hard coatings: Structure, mechanical properties and growth defect related salt spray test results N2 - Hard and wear resistant coatings deposited by PVD techniques have been characterized for decades for their capabilities to protect steel substrates from corrosion. In the present work the effect of Mg incorporated into TiN coatings is described in terms of the corrosion behavior as well as the mechanical and structural properties. TiN and TiMgN films with Mg contents between 10 and 35 at.% were deposited onto mirror polished 100Cr6 (1.3505) steel samples with 2.5 and 5 μm thickness by using DC magnetron sputtering. The corrosion protection capabilities of the coatings were characterized by neutral salt spray (NSS) test, considering the amounts and sizes of growth defects inherent in each coated sample as determined by a recently developed optical scan method (Large Area High Resolution mapping). The defect data were statistically analyzed for improved interpretation of NSS test results. Chosen growth defects were additionally analyzed by focused ion beam technique. Furthermore the coating composition and morphology, the hardness and the tribological behavior were characterized. Polished steel samples coated with 2.5 μm TiMgN containing about 35 at.% Mg were in the plane free of corrosion after 24 h in a NSS test. TiMgN with 10 or 20 at.% Mg only provided a slightly improved corrosion protection in relation to pure TiN coatings, which was limited to certain types of growth defects. The highest Mg containing coatings exhibited a decreased hardness down to 1200 or 1800 HV depending on type of deposition (HV 1200: Ti- and Mg-target with rotating substrate holder, 1800: Mg-plugged Ti-target with static substrate holder), but also showed a strongly improved wear resistance against Al2O3 related to pure TiN. By analyzing the NSS test results it was found that the corrosion behavior of the coated samples did not only depend strongly on the Mg content, but also on the sample individual defect concentrations. Therefore this subject is extensively discussed. KW - Physical vapour deposition (PVD) KW - Corrosion KW - Growth defects KW - Pinholes KW - Magnesium KW - TiMgN PY - 2018 DO - https://doi.org/10.1016/j.surfcoat.2018.05.037 SN - 0257-8972 VL - 349 IS - 9 SP - 82 EP - 92 PB - Elsevier B.V. AN - OPUS4-45712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael A1 - Wetzel, Annica A1 - Oczan, Ozlem A1 - Nietzke, Jonathan A1 - Richter, Tim A1 - Schröpfer, Dirk T1 - Hydrogen diffusion and local Volta potential in high- and medium-entropy alloys N2 - High-entropy alloys (HEAs) are characterized by a solid solution of minimum five and medium-entropy alloys (MEAs) of minimum three principal alloying elements in equiatomic proportions. They show exceptional application properties, such as high-strength and ductility or corrosion resistance. Future HEA/MEA-components could be exposed to hydrogen containing environments like vessels for cryogenic or high-pressure storage where the hydrogen absorption and diffusion in these materials is of interest. In our study, we investigated the HEA Co20Cr20Fe20Mn20Ni20 and the MEA Co33.3Cr33.3Ni33.3. For hydrogen ingress, cathodic charging was applied and diffusion kinetic was measured by high-resolution thermal desorption spectros-copy using different heating rates up to 0.250 K/s. Peak deconvolution resulted in high-temperature desorption peaks and hydrogen trapping above 280 °C. A total hydrogen concentration > 40 ppm was identified for the MEA and > 100 ppm for HEA. This indicates two important effects: (1) delayed hydrogen diffusion and (2) considerable amount of trapped hydrogen that must be anticipated for hydrogen assisted cracking phenomenon. Local electrochemical Volta potential maps had been measured for the hydrogen free condition by means of high-resolution Scanning Kelvin Probe Force Microscopy (SKPFM). T2 - Symposium on Materials and Joining Technology CY - Online meeting DA - 07.09.2020 KW - Hydrogen KW - High-entropy alloy KW - Diffusion KW - Scanning kelvin probe force microscopy KW - Corrosion PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511684 DO - https://doi.org/10.1088/1757-899X/882/1/012015 VL - 882 SP - 1 EP - 15 PB - IOP Publishing CY - Bristol AN - OPUS4-51168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Babutzka, Martin A1 - Müller, Thoralf A1 - Mietz, Jürgen A1 - Burkert, Andreas T1 - Investigation of the influence of iron‐containing abrasives on the corrosion behaviour of the aluminium alloy AlSi1.2Mg0.4 N2 - The corrosion resistance of aluminium surfaces is closely linked to the surfacecstate after a grinding process. For years, iron‐containing abrasive materials were suspected to lead to increased corrosion susceptibility after processing of aluminium surfaces. To prove a possible correlation between the iron content of an abrasive and the corrosion behaviour of aluminium components, scientific investigations and experimentally practical corrosion tests are necessary. For the current investigation, specimens of a technical Al‐Si alloy from the same batch were used. The test specimens were mechanically ground with various resin‐bonded model abrasives containing different iron contents. The performed corrosion tests did not reveal a negative influence of the different iron‐containing abrasives on the corrosion behaviour of the Al–Si alloy. However, the most sensitive measuring method (electrochemical noise) showed differences in the surface activity depending on the type of abrasive. KW - Aluminium KW - Corrosion KW - Corrosion testing KW - Grinding PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506762 DO - https://doi.org/10.1002/maco.202011657 SN - 0947-5117 SN - 1521-4176 VL - 71 IS - 10 SP - 1667 EP - 1679 PB - Wiley‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50676 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Boschmann Käthler, C. A1 - Angst, U. A1 - Ebell, Gino A1 - Elsener, B. T1 - Chloride-induced reinforcement corrosion in cracked concrete: the influence of time of wetness on corrosion propagation N2 - Literature data on the influence of concrete cracks on corrosion propagation of reinforcing steel are contradictory. This might be due to very different exposure and test conditions but also to a lack of time-resolved data in cyclic wetting–drying exposure. Here, the influence of the environmental conditions on the corrosion rates in cracked concrete is studied experimentally. The results show that the corrosion rate in cracked concrete depends on the duration of wetting and drying phases and the relative humidity (RH) during the drying phase. The lower the ambient RH in the drying phase, the faster the cracks dry, which depresses the corrosion rate in the periods between the wetting events. A model is proposed to estimate corrosion rates in cracked concrete cyclic wetting/drying exposure. KW - Korrosion KW - Corrosion KW - Concrete PY - 2020 DO - https://doi.org/10.1080/1478422X.2020.1789371 SP - 1 EP - 11 PB - Taylor Francis Online CY - London AN - OPUS4-50986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -