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 JF - Materials and Corrosion 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 JF - Journal of Electroanalytical Chemistry 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 - Ebell, Gino A1 - Mayer, T. F. A1 - Harnisch, J. A1 - Dauberschmidt, Ch. T1 - Corrosion monitoring of reinforced concrete structures:The DGZfP specification B12 Collaboration JF - Materials and Corrosion 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 - Bäßler, Ralph A1 - Bettge, Dirk A1 - Bender, R. A1 - Féron, D. A1 - Mills, D. A1 - Ritter, S. A1 - de Graeve, I. A1 - Dugstad, A. A1 - Grassini, S. A1 - Hack, T. A1 - Halama, M. A1 - Han, E.-H. A1 - Harder, T. A1 - Hinds, G. A1 - Kittel, J. A1 - Krieg, R. A1 - Leygraf, C. A1 - Martinelli, L. A1 - Mol, A. A1 - Neff, D. A1 - Nilsson, J.-O. A1 - Odnevall, I. A1 - Paterson, S. A1 - Paul, S. A1 - Prosek, T. A1 - Raupach, M. A1 - Revilla, R. I. A1 - Ropital, F. A1 - Schweigart, H. A1 - Szala, E. A1 - Therryn, H. A1 - Tidblad, J. A1 - Virtanen, S. A1 - Volovitch, P. A1 - Watkinson, D. A1 - Wilms, M. A1 - Winning, G. A1 - Zheludkevich, M. T1 - La corrosion: un défi pour une société durable JF - Techniques de l'ingenieur N2 - Une transition mondiale vers des systèmes énergétiques plus durables, abordables et fiables a été initiée par l’accord de Paris et l’Agenda 2030 des Nations unies pour un développement durable. Il s’agit là d’un défi industriel majeur car les systèmes et infrastructures énergétiques résilients au changement climatique exigent de se positionner pour le long terme. Se pencher sur le comportement dans la durée des matériaux structurels - principalement des métaux et des alliages - s’impose alors comme une nécessité. Dans cette optique, « La corrosion : un défi pour une société durable »présente une série de cas montrant l’importance de la tenue à la corrosion et de la protection anticorrosion des métaux et des alliages pour le développement de systèmes durables, économiques et fiables de production d’énergie. KW - Corrosion KW - Coûts de la corrosion KW - Protection KW - Anticorrosion KW - Stratégies deprévention PY - 2023 DO - https://doi.org/10.51257/a-v1-cor2000 SN - 2555-5383 VL - 2023 IS - Avril SP - 1 EP - 23 CY - Saint-Denis, France AN - OPUS4-57927 LA - fra AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwarz, W. A1 - Wilsch, Gerd A1 - Katsumi, N. A1 - Ebell, Gino A1 - Völker, Tobias T1 - Ion distribution in concrete overlay, mapped by laser induced breakdown spectroscopy (LIBS), modified by an embedded zinc anode JF - MATEC web of conferences N2 - Galvanic corrosion protection by embedded zinc anodes is an accepted technique for the corrosion protection of reinforcing steel in concrete. Galvanic currents flow between the zinc anode and the steel reinforcement due to the potential difference that is in the range of a few hundred mV. The ion distribution was studied on two steel reinforced concrete specimens admixed with 3 wt.% chloride/wt. cement and galvanically protected by a surface applied EZ-anode. On both specimens, a zinc anode was embedded and glued to the concrete surface by a geo-polymer-based chloride-free binder. At one specimen, the EZ-anode was operated for 2,5 years, the EZ-anode at the other specimen was not electrically connected to the reinforcement, this specimen serves as a reference. Both specimens have been stored under identical conditions. The ion distribution between the anode (EZ-ANODE) and cathode (steel reinforcement) was studied by laser-induced breakdown spectroscopy (LIBS) after 7 months, 12 months, and 2,5 years. Results of the LIBS studies on the specimen with activated EZ-anode after 7 months, 12 months, and 2,5 years and of the reference specimen after 2,5 years are reported. Results show that diffusion of ions contributes to the changes in the ion distribution but migration, especially of chlorides towards the EZ-anode is significant despite the weak electric field – several hundred millivolts - generated by the galvanic current. Results show that chloride ions accumulate near the zinc-anode as in water-insoluble zinc-hydroxy chlorides - Simonkollite. T2 - ICCRRR 2022 CY - Capetown, South Africa KW - Corrosion KW - LIBS KW - Zinc KW - Anode PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-560576 DO - https://doi.org/10.1051/matecconf/202236404023 SN - 2261-236X VL - 364 SP - 1 EP - 7 PB - EDP Sciences CY - Les Ulis AN - OPUS4-56057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bender, R. A1 - Féron, D. A1 - Mills, D. A1 - Ritter, S. A1 - Bäßler, Ralph A1 - Bettge, Dirk A1 - de Graeve, I. A1 - Dugstad, A. A1 - Grassini, S. A1 - Hack, T. A1 - Halama, M. A1 - Han, E.-H. A1 - Harder, T. A1 - Hinds, G. A1 - Kittel, J. A1 - Krieg, R. A1 - Leygraf, C. A1 - Martinelli, L. A1 - Mol, A. A1 - Neff, D. A1 - Nilsson, J.-O. A1 - Odnevall, I. A1 - Paterson, S. A1 - Paul, S. A1 - Prošek, T. A1 - Raupach, M. A1 - Revilla, R. I. A1 - Ropital, F. A1 - Schweigart, H. A1 - Szala, E. A1 - Terryn, H. A1 - Tidblad, J. A1 - Virtanen, S. A1 - Volovitch, P. A1 - Watkinson, D. A1 - Wilms, M. A1 - Winning, G. A1 - Zheludkevich, M. T1 - Corrosion challenges towards a sustainable society JF - Materials and corrosion N2 - A global transition towards more sustainable, affordable and reliable energy systems is being stimulated by the Paris Agreement and the United Nation's 2030 Agenda for Sustainable Development. This poses a challenge for the corrosion industry, as building climate‐resilient energy systems and infrastructures brings with it a long‐term direction, so as a result the long‐term behaviour of structural materials (mainly metals and alloys) becomes a major prospect. With this in mind “Corrosion Challenges Towards a Sustainable Society” presents a series of cases showing the importance of corrosion protection of metals and alloys in the development of energy production to further understand the science of corrosion, and bring the need for research and the consequences of corrosion into public and political focus. This includes emphasis on the limitation of greenhouse gas emissions, on the lifetime of infrastructures, implants, cultural heritage artefacts, and a variety of other topics. KW - Corrosion KW - Corrosion costs KW - Corrosion protection KW - Preventive strategies PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-554801 DO - https://doi.org/10.1002/maco.202213140 SN - 1521-4176 VL - 73 IS - 11 SP - 1730 EP - 1751 PB - Wiley-VCH CY - Weinheim AN - OPUS4-55480 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Babutzka, Martin A1 - Grabowski, Sven A1 - Sahrhage, H. A1 - Lampke, T. T1 - Electrochemical corrosion investigations on binary and ternary zinc alloy coatings using gel electrolytes JF - Advanced engineering materials N2 - Novel agar-based test electrolytes are used to perform electrochemical corrosion investigations on ZnFe and ZnNi binary as well as ZnFeMo ternary zinc coatings. The objectives of the electrochemical investigations include the characterization of the corrosion behavior, the description of the protective effect of the coatings as well as the investigation of the layer formation and degradation under artificial aging. ZnFe and ZnFeMo coatings are applied with varying iron content as well as an additional passivation layer, respectively, to study the effect on corrosion resistance. The results show that the protective effect of the coatings is not negatively influenced by different iron contents or the addition of molybdenum. Additional passivation of the ZnFe-containing coatings by means of a passivating agent leads to a significant improvement in the protective effect. Artificial aging leads to slight degradation of the additional passivation layer whereas coatings without post-treatment enhance their protective effect by the formation of corrosion product layers. KW - Binary zinc alloys KW - Ternary zinc alloys KW - Corrosion testing KW - Gel electrolytes KW - Corrosion PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543013 DO - https://doi.org/10.1002/adem.202101336 SN - 1438-1656 SP - 1 EP - 14 PB - Wiley-VCH CY - Weinheim AN - OPUS4-54301 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Aristia, Gabriela A1 - Bäßler, Ralph A1 - Nofz, Marianne A1 - Sojref, Regine A1 - Kohl, Anka T1 - Short-term exposure tests of ɣ-Al2O3 Sol-gel coating on X20Cr13 in artificial geothermal waters with different pH JF - Geothermics N2 - The suitability of an Al2O3 coating for corrosion protection on X20Cr13 was evaluated in various artificial geothermal brines, focusing on the influence of different pH (4, 6 and 8) and their chemical compositions on the coating properties. All experiments were performed in the laboratory using autoclaves at 150 ◦C and 1 MPa in deaerated condition for 1 and 7 days. Results showed that the pH of geothermal waters is the most detrimental factor in the transformation of ɣ-Al2O3 and its protective abilities. Delaminations were found in the Coating exposed to geothermal brines with pH 4. FTIR spectra indicated a transformation of ɣ-Al2O3 to boehmite AlOOH after exposure to pH 4 and 6, and bayerite Al(OH)3 was formed after exposure to pH 8. Different Crystal structures of the hydrated Al2O3 also contribute to the stability of the coatings, observed by the SEM- EDX of the surface and cross-section of coatings. This study indicated that ɣ-Al2O3 sol-gel coating presents a promising aspect of corrosion protection in geothermal environment with a neutral pH. KW - Al2O3 KW - Corrosion KW - Coating KW - Martensitic steel PY - 2021 DO - https://doi.org/10.1016/j.geothermics.2021.102193 SN - 0375-6505 VL - 96 SP - 102193 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-52931 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Valet, Svenja A1 - Burkert, Andreas A1 - Ebell, Gino A1 - Babutzka, Martin T1 - Determination of the corrosion product layer resistance on zinc and electrolytically galvanized steel samples by using gel electrolytes JF - Electrochimica Acta N2 - Although zinc and zinc coatings have been widely used for corrosion protection for decades new zinc coatings are constantly being developed. Characterizing the corrosion protectiveness of these new coatings, however, should not be underestimated. While exposure tests are time intensive, cyclic tests can only be used for a very limited field of application. Thus, electrochemical measurements provide both an efficient and an effective alternative. Conventional aqueous bulk electrolytes influence the surface layers of a tested zinc coating and are therefore not reliable. Gel electrolytes, however, have evolved over the last few years, are minimally invasive and provide reliable results. This work describes experiments with gel electrolytes made of agar. Unlike previous work, it proposes a composition of gel electrolyte for minimally invasive description of the protective power of naturally formed oxide layers on zinc and zinc coatings. Therefore, as a first part, the gel electrolyte made of agar is verified as a method for zinc and zinc-coated samples. Afterwards, this paper introduces the corrosion product layer resistance RL as a promising parameter to evaluate the protective power of zinc coatings. Results are verified with EIS and FTIR measurements. An example on a representative zinc coating demonstrates the practical application. KW - Gel electrolytes KW - Agar KW - Zinc coatings KW - Atmospheric exposure KW - Corrosion PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-526053 DO - https://doi.org/10.1016/j.electacta.2021.138191 SN - 0013-4686 VL - 385 SP - 138191 PB - Elsevier Ltd. AN - OPUS4-52605 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Aristia, Gabriela A1 - Le, Quynh Hoa A1 - Nofz, Marianne A1 - Sojref, Regine A1 - Bäßler, Ralph T1 - Study of Al2O3 Sol-Gel Coatings on X20Cr13 in Artificial North German Basin Geothermal Water at 150 °C JF - Coatings N2 - Al2O3 has been widely used as a coating in industrial applications due to its excellent chemical and thermal resistance. Considering high temperatures and aggressive mediums exist in geothermal systems, Al2O3 can be a potential coating candidate to protect steels in geothermal applications. In this study, γ-Al2O3 was used as a coating on martensitic steels by applying AlOOH sol followed by a heat treatment at 600 °C. To evaluate the coating application process, one-, two-, and three-layer coatings were tested in the artificial North German Basin (NGB), containing 166 g/L Cl−, at 150 °C and 1 MPa for 168 h. To reveal the stability of the Al2O3 coating in NGB solution, three-layer coatings were used in exposure tests for 24, 168, 672, and 1296 h, followed by surface and cross-section characterization. SEM images show that the Al2O3 coating was stable up to 1296 h of exposure, where the outer layer mostly transformed into boehmite AlOOH with needle-like crystals dominating the surface. Closer analysis of cross-sections showed that the interface between each layer was affected in long-term exposure tests, which caused local delamination after 168 h of exposure. In separate experiments, electrochemical impedance spectroscopy (EIS) was performed at 150 °C to evaluate the changes of coatings within the first 24 h. Results showed that the most significant decrease in the impedance is within 6 h, which can be associated with the electrolyte penetration through the coating, followed by the formation of AlOOH. Here, results of both short-term EIS measurements (up to 24 h) and long-term exposure tests (up to 1296 h) are discussed. KW - Al2O3 KW - Geothermal KW - Martensitic steels KW - Behmite KW - Corrosion PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-525551 DO - https://doi.org/10.3390/coatings11050526 SN - 2079-6412 VL - 11 IS - 5 SP - 526 PB - MDPI CY - Basel AN - OPUS4-52555 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -