TY - JOUR A1 - Kauss, Norman A1 - Heyn, A. A1 - Michael, O. A1 - Schymura, M. A1 - Rosemann, P. T1 - Application limits and sensitisation behaviour of the manganese- and nitrogen-alloyed austenitic stainless steel P2000 (X13CrMnMoN18-14-3) N2 - Nickel‐free high‐nitrogen‐alloyed stainless steels like the P2000 (X13CrMnMoN18‐14‐3) were developed to enhance the strength and corrosion resistance of austenitic stainless steels like 304 and 316 while keeping the typical high ductility. The mechanical and corrosive properties of P2000 were investigated and compared with 304 and 316 to highlight the application opportunities of this new alloy. The microstructure of the solution‐annealed condition was characterised by electron backscatter diffraction and the mechanical properties were studied by uniaxial tensile tests, Charpy impact tests and hardness measurements. The passivation behaviour was analysed using the electrochemical potentiodynamic reactivation, whereas the pitting corrosion resistance was compared by pitting potentials and pitting temperatures. However, secondary thermal influences or suboptimal heat treatment can impair the corrosion resistance due to the precipitation of secondary phases and the resulting sensitisation. Thermodynamic calculations and artificial ageing treatment in the range of 500–900°C for up to 100 h were used to determine critical time–temperature parameters for sensitisation. The microstructure of the various aged states was evaluated by scanning electron microscopy and compared with the degrading corrosion resistance characterised by the KorroPad method. KW - Austenitic stainless steel KW - Electrochemical methods KW - High‐nitrogen steel KW - Mechanical properties KW - Corrosion resistance PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527925 DO - https://doi.org/10.1002/maco.202112450 VL - 71 IS - 10 SP - 1656 EP - 1667 PB - Wiley-VCH GmbH AN - OPUS4-52792 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rütters, H. A1 - Fischer, S. A1 - Le, Quynh Hoa A1 - Bettge, Dirk A1 - Bäßler, Ralph A1 - Maßmann, J. A1 - Ostertag-Henning, C. A1 - Wolf, J. L. A1 - Pumpa, M. A1 - Lubenau, U. A1 - Knauer, S. A1 - Jaeger, P. A1 - Neumann, A. A1 - Svensson, K. A1 - Pöllmann, H. A1 - Lempp, C. A1 - Menezes, F. F. A1 - Hagemann, B. T1 - Towards defining reasonable minimum composition thresholds – Impacts of variable CO2 stream compositions on transport, injection and storage N2 - To set up recommendations on how to define “reasonable minimum composition thresholds” for CO2 streams to access CO2 pipeline networks, we investigated potential impacts of CO2 streams with different and temporally variable compositions and mass flow rates along the CCS chain. All investigations were based on a generic “CCS cluster scenario” in which CO2 streams captured from a spatial cluster of eleven emitters (seven fossil-fired power plants, two cement plants, one refinery and one steel mill) are collected in a regional pipeline network. The resulting CO2 stream (19.78 Mio t impure CO2 per year) is transported in a trunk line (onshore and offshore) and injected into five generic replicate storage structures (Buntsandstein saline aquifers) offshore. Experimental investigations and modeling of selected impacts revealed beneficial as well as adverse impacts of different impurities and their combinations. Overall, no fundamental technical obstacles for transporting, injecting and storing CO2 streams of the considered variable compositions and mass flow rates were observed. We recommend to define minimum composition thresholds for each specific CCS project through limiting i) the overall CO2 content, ii) maximum contents of relevant impurities or elements, iii) acceptable variability of concentrations of critical impurities, and defining impurity combinations to be avoided. KW - Impurities KW - CO2 quality KW - Pipeline network KW - Whole-chain CCS scenario KW - Recommendations PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543004 DO - https://doi.org/10.1016/j.ijggc.2022.103589 SN - 1750-5836 VL - 114 SP - 1 EP - 14 PB - Elsevier CY - New York, NY AN - OPUS4-54300 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Haacke, Nasrin A1 - Paton, E. T1 - Impact-based classification of extreme rainfall events using a simplified overland flow model N2 - In this study, we present a new rainfall classification method based on the potential of individual rainstorm events to generate and sustain overland flow on a simplified urban model surface. Conventional rainfall classification approaches using peak intensities or rainfall sums can lead to mis-judgements of the impact of rainfall events, as they do not explicitly consider the potential of rain to generate and sustain substantial amounts of overland flow on typical sealed urban surfaces. The new method of impact-based rainfall classification proposed here comprises three steps: Identification of rainfall events from high-resolution time series, computation of overland flow depths for each event, and impact-based classification of rainfall events as a function of the magnitude of overland flow. The accuracy of this approach was evaluated by its ability to describe seasonal and annual occurrences of and variations in rainstorm impacts for high-resolution series at three different urban stations in Germany. KW - Flow depth KW - Impact assessment KW - Overland flow KW - Urban flooding KW - Rainfall classification PY - 2023 DO - https://doi.org/10.1080/1573062X.2022.2164731 SP - 1 EP - 11 PB - Taylor & Francis Group CY - London AN - OPUS4-56794 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 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 - Babutzka, Martin A1 - Lehmann, Jens A1 - Burkert, Andreas T1 - Field exposure study under sheltered and open exposure conditions at different test sites in Germany: First‐year corrosion rate and atmospheric corrosivity N2 - The corrosivity of atmospheres in Europe has changed significantly in recent decades. For the Federal Republic of Germany, no current values for the corrosion rate based on 1‐year atmospheric exposure of standard specimens can be found in the scientific literature after 2000. This paper presents results from a field exposure study in the Berlin metropolitan area and Helgoland in 2016. Based on standard specimens, values for the corrosion rate and the corresponding atmospheric corrosivity category are determined for open exposure and indirect weathering in a ventilated enclosure as sheltering after 1 year of exposure. The results prove that determined corrosivity categories are material‐specific. Sheltered exposure is a typical atmospheric situation for many building components. It allows statements on the effect of the concentration of airborne substances on the corrosivity beyond the normative requirements. KW - Atmospheric corrosion KW - Corrosivity category KW - ISO 9223 KW - Mass loss KW - Atmosphärische Korrosion PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565099 DO - https://doi.org/10.1002/maco.202213582 SN - 0947-5117 (print) SN - 1521-4176 (online) SP - 1 EP - 15 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-56509 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erning, Johann Wilhelm A1 - Kamaraj, A. T1 - Susceptibility of 304 Stainless Steel to Crevice Corrosion in Electrochemically Active Fluids N2 - The susceptibility of Type 304 stainless steel (SS) to crevice corrosion upon contacting with electrochemically active fluids was investigated using exposure tests and stepwise potentiostatic polarization. Crevice materials made of 304 SS and polyether ether ketone (PEEK) were focused on in this study. The combined influence of oxidant and chloride concentration on crevice corrosion was examined in detail in the two types of crevice combinations (304 SS-to-PEEK and 304 SS-to-304 SS). The 304 SS specimens were strongly susceptible to crevice corrosion when coupled with 304 SS. Even at a low concentration of 5 mg/L free chlorine and 150 mg/L chloride, which is below nominal dilutions in beverage industries, the examined specimens underwent crevice corrosion in both crevices. The effect of water composition on crevice corrosion was also studied, indicating high susceptibility of 304 SS to crevice corrosion in low pH (pH ≤ 5) solutions. The corroded surface morphology was analyzed using scanning electron microscope, energy dispersive x-ray, and confocal. KW - Crevice corrosion KW - Disinfectants KW - Stainless steel PY - 2020 DO - https://doi.org/10.5006/3324 SN - 0010-9312 VL - 76 IS - 4 SP - 424 EP - 435 PB - Nace International CY - Houston AN - OPUS4-50652 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seifert, Lando A1 - Grunewald, Andreas A1 - Müller, Thoralf A1 - Ebell, Gino T1 - Stress corrosion tests for prestressing steels—Part 1: The influence of surface condition and test solution composition on hydrogen charging N2 - Tests for assessing prestressing steels' susceptibility to hydrogen‐induced stress corrosion cracking are essential for approvals, in‐house monitoring, and third‐party material testing. According to ISO 15630‐3, the time to brittle fracture by constant load under corrosive conditions in thiocyanate test solutions (A or B) at 50°C is measured. In the literature, a high scattering in stress corrosion tests is reported, which questions the integrity of the test procedure. This paper shows the results of studies about the influence of solution composition on hydrogen charging in electrochemical and permeation measurements. Electrochemical experiments show that polished steel surfaces without common drawing layers have more consistent free corrosion currents, polarization resistances, and B‐values in solution A with low scattering compared to the solution B experiments. The influence of temperature at 50°C and an ambient temperature of 22°C was also tested. KW - Drawing layers KW - Hydrogen‐induced stress corrosion cracking KW - Permeation measurements KW - Prestressing steels KW - Stress corrosion tests KW - Surface conditions KW - Test solutions PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598738 DO - https://doi.org/10.1002/maco.202313948 VL - 75 SP - 1506 EP - 1518 PB - Wiley‐VCH GmbH AN - OPUS4-59873 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Marx, S. A1 - Scheerer, S. A1 - Schacht, G. A1 - Fiedler, M. A1 - Ritter, R. A1 - Clages, L. A1 - Voigt, C. A1 - Czeschka, D. A1 - Ebell, Gino A1 - Marzahn, G. T1 - Einsturz der Carolabrücke in Dresden Teil 1 T1 - Collapse of the Carola Bridge in Dresden Part 1: From theambitious design to the tragic partial collapse N2 - AbstraktDer 11. September 2024 wird nicht nur der Brückenbaucommunity in Deutschland in Erinnerung bleiben. Der Teileinsturz einer Spannbetonbrücke ohne Vorankündigung schlug berechtigterweise gesamtgesellschaftlich hohe Wellen. Betroffen war die Dresdner Carolabrücke – ein ästhetisches und ausgesprochen schlankes Bauwerk, welches in der Fachwelt zurecht als eine Ikone der Ingenieurbaukunst ihrer Zeit angesehen wird. Die Konstruktion sowie der Bau wären auch unter den heutigen Möglichkeiten eine Herausforderung. Der vorliegende Teil 1 des Beitrags fasst die Entstehungsgeschichte, die Konstruktion selbst und den Bau der Brücke zusammen. Es werden die Maßnahmen zur Instandhaltung und Sanierung der Brücke vorgestellt. In einem Teil 2 wird der Versuch der Rekonstruktion des Einsturzvorgangs unternommen und die Suche nach der Einsturzursache beschrieben. Zudem wird auf das aktuelle Monitoring eingegangen und ein Ausblick auf das mögliche weitere Vorgehen gegeben. KW - Korrosion KW - Spannungsrisskorrosion KW - Spannstahl KW - Wasserstoff PY - 2025 DO - https://doi.org/10.1002/best.202500029 SN - 0005-9900 VL - 120 IS - 7 SP - 526 EP - 536 PB - Wiley AN - OPUS4-63411 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Thoralf A1 - Ebell, Gino A1 - Burkert, Andreas T1 - Risiko der Wasserstoffentwicklung an martensitischen Schraubankern unter baupraktischen Bedingungen T1 - Risk of hydrogen evolution on martensitic screw anchors under practical construction conditions N2 - Die vorliegende Untersuchung beschäftigt sich mit der Fragestellung, ob unter praxisrelevanten Bedingungen die Entstehung von Wasserstoff an vollmartensitischen Schraubankern möglich ist. Im Gegensatz zu austenitischen Werkstoffen besteht bei martensitischen Werkstoffen bei Gegenwart von Wasserstoff stets die Möglichkeit einer wasserstoffinduzierten Versprödung des Materials. Hierfür wurde ein in der Praxis häufig anzutreffendes Szenario gewählt, das ein galvanisches Element, bestehend aus nichtrostenden Schraubankern (in diesem Fall martensitischen) und einer verzinkten Ankerplatte an einem Betonkörper, umfasst. Zum Nachweis einer Wasserstoffentwicklung werden der Elementstrom zwischen den Bauteilen sowie das Korrosionspotential erfasst. Die Ergebnisse der Versuche zeigen, dass über eine zeitlich begrenzte Dauer eine starke kathodische Polarisation der martensitischen Schraubanker durch die korrosive Auflösung des Zinks erfolgt. Als Folge kommt es zur Wasserzersetzung im Phasengrenzbereich der Schraubanker und zur Entstehung von atomarem Wasserstoff. Das berechnete Gasvolumen des entstandenen Wasserstoffs an den Stahlankern wurde bestimmt und lag im Mittel bei 11,14 ± 1,94 ml. Eine Diffusion des an der Stahloberfläche adsorbierten Wasserstoffs in den martensitischen Werkstoff ist somit theoretisch möglich und impliziert eine mögliche Gefährdung durch wasserstoffinduzierte Rissbildung und spontanes Versagen unter Belastung. N2 - The present investigation deals with the question of whether the formation of hydrogen is possible on fully martensitic screw anchors under practical conditions. In contrast to austenitic materials, martensitic steels always have the possibility of hydrogen-induced embrittlement of the material in the presence of hydrogen. For this purpose, a scenario was chosen which is frequently encountered in practice and which comprises a galvanic element consisting of stainless screw anchors (in this case martensitic) and a galvanized anchor plate on a concrete body. The element current between the components as well as the corrosion potential are recorded to prove hydrogen development. The results of the tests show that a strong cathodic polarization of the martensitic screw anchors occurs over a limited period due to the corrosive dissolution of the zinc. As a result, water decomposition occurs in the phase boundary area of the screw anchors and atomic hydrogen is formed. The calculated gas volume of the resulting hydrogen at the steel anchors was determined and was 11.14 +/- 1.94 ml on average. Diffusion of the hydrogen adsorbed on the steel surface into the martensitic material is thus theoretically possible and implies a possible risk of hydrogen-induced crack formation and spontaneous failure under load. KW - Martensit KW - Wasserstoff KW - Versprödung KW - Beton KW - Korrosion PY - 2020 DO - https://doi.org/10.1002/bate.202000017 SN - 0932-8351 SN - 1437-0999 VL - 97 SP - 1 EP - 7 PB - Wiley CY - Weinheim AN - OPUS4-50799 LA - deu 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 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 - Heyn, A. A1 - Kotula, Stefan A1 - Ebell, Gino A1 - Babutzka, M. T1 - Results of a Round Robin Test for the Determination of Polarization Resistances on Differently Weathered Zinc Samples Using Gel Electrolytes N2 - This article presents the results of a round robin test throughout Germany with 19 participating institutions. Corrosion productlayer resistances (RL ) were determined on two differently weathered pure zinc samples and a sample activated with NaOH bymeans of electrochemical measurement of the linear polarization resistance (LPR) using agar‐based gel electrolytes. The roundrobin test was organized by the Bundesanstalt für Materialforschung und ‐prüfung (BAM) in Berlin. The measurements werecarried out by the participants in the period from May to July 2021. The results are summarized in this article comprising anassessment of the reproducibility and repeatability of the measurements. The methodology is suitable for distinguishing zincsurfaces after exposure to different atmospheres based on the corrosion product layer resistances (RL). In addition, possibleproblems in the application of the method were identified, and solutions for improving reproducibility and repeatability arediscussed. The results and knowledge from the round robin test are incorporated into a new test standard (DIN 50023:2024‐07)for this measurement method KW - Corrosion PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630546 DO - https://doi.org/10.1002/maco.202414696 SN - 1521-4176 SP - 1 EP - 12 PB - Wiley AN - OPUS4-63054 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 - Kaplan, F. A1 - Steinbock, O. A1 - Saloga, K. A1 - Ebell, Gino A1 - Schmidt, S. T1 - Überwachung der Brücke am Altstädter Bahnhof T1 - Monitoring of the bridge at the Altstadter Bahnhof in Brandenburg a. d. Havel N2 - Die B 1-Brücke am Altstädter Bahnhof war der wichtigste Verkehrsknotenpunkt in Brandenburg an der Havel. Im Dezember 2019 wurden die überführte Bundesstraße und die Straßenbahnlinie für den Verkehr gesperrt. Grund für die Sperrung war eine einsetzende Rissbildung in den Längsträgerstegen in Verbindung mit Hohlstellen, die letztlich auf gerissene Spanndrähte zurückgeführt werden. Um eine Sperrung der hoch frequentierten unterführten Verkehrswege zu verhindern, wurde ein umfangreiches Überwachungskonzept erforderlich. Wesentlicher Bestandteil dieses Konzepts war ein auf der Schallemissionsanalyse basierendes Monitoringsystem, mit dessen Hilfe Spanndrahtbrüche aufgezeichnet und lokalisiert werden konnten. Auf Grundlage der so gewonnenen Ergebnisse konnten Schwerpunkte für die Bauwerksprüfung abgeleitet werden. In diesem Bericht werden die gewonnenen Erkenntnisse zum messtechnisch erfassten Schadensfortschritt und den damit verbundenen visuell festgestellten Schäden beschrieben. Dabei werden die Besonderheit des verbauten konzentrierten Spannglieds (Spannblockverfahren nach TGL 173-33) und des Spannstahls in Bezug auf die Schadensbilder dargestellt. Die gewonnenen Erkenntnisse sollten bei der Beurteilung anderer Bauwerke mit vergleichbarer Bauart berücksichtigt werden. KW - Korrosion KW - Spannstahl KW - Spannungsrisskorrosion PY - 2022 DO - https://doi.org/10.1002/bate.202200008 SN - 0932-8351 VL - 99 IS - 3 SP - 222 EP - 230 PB - Ernst & Sohn AN - OPUS4-54485 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steinbock, O. A1 - Bösche, T. A1 - Ebell, Gino A1 - Kaplan, F. A1 - Marzahn, G. T1 - Erfahrungen aus dem Rückbau der Brücke am Altstädter Bahnhof in der Stadt Brandenburg N2 - Bei der Brücke Altstädter Bahnhof handelte es sich um eine große Spannbetonkonstruktion, die einen elementaren Ver­kehrsknotenpunkt in der Stadt Brandenburg an der Havel bil­dete. Entgegen üblichen Spannbetonkonstruktionen mit kleinen Bündelspanngliedern kamen beim Haupttragwerk in Längsrich­tung großformatige Spannblockspannglieder zum Einsatz. Im Fall der vorliegenden Brücke setzte sich das Spannglied aus 392 ovalen Einzeldrähten aus Hennigsdorfer Produktion zusam­men, welche als spannungsrisskorrosionsgefährdet gelten. Bei Bauwerkserkundungen wurde ein hoher Versprödungsgrad der Spannstähle festgestellt, sodass die Brücke am 19.05.2021 ge­sprengt werden musste. Zuvor traten im Bereich detektierter Spanndrahtbrüche von außen erkennbare Längsrisse in den Stegen anstatt von üblicherweise quer gerichteten Biegerissen an der gezogenen Randfaser auf. Die abweichende Schadens­äußerung im Falle einer Spannstahlschädigung brachte das Bundesministerium für Digitales und Verkehr (BMDV) dazu, weitergehende Untersuchungen durchzuführen. In Zusammen­arbeit mit dem Landesbetrieb Straßenwesen Brandenburg, der Hochschule für Technik und Wirtschaft Dresden sowie der Bundesanstalt für Materialforschung und ­prüfung (BAM) wur­den experimentelle Untersuchungen in­situ konzipiert und durchgeführt. Im Konkreten wurde an zwei Messstellen eine gezielte Schädigung des großformatigen Spannglieds vorge­nommen, um das zuvor vorgefundene Schadensbild nach­zuvoll ziehen und validieren zu können. Konzept, Ergebnisse aus den Untersuchungen und Erkenntnisse für gleichartig ausge­führte Bauwerke sind Gegenstand des ersten Beitrags (Teil 1). Der zweite Teil [1] wird sich im Schwerpunkt den verwendeten Messverfahren und Monitoringsystemen widmen, welche die Durchführung des Versuchs begleiteten. KW - Korrosion KW - Spannungsrisskorrosion KW - Spannstahl KW - Wasserstoff PY - 2022 DO - https://doi.org/10.1002/best.202200051 VL - 117 IS - 1 SP - 572 EP - 580 PB - Ernst & Sohn CY - Berlin AN - OPUS4-55329 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seifert, Lando A1 - Müller, Thoralf A1 - Bettge, Dirk A1 - Moersch, Jörg A1 - Isecke, Bernd A1 - Ebell, Gino T1 - Stress Corrosion Tests for Prestressing Steels—Part 2: Susceptibility of Quenched and Tempered Wires—Influence of Chromium N2 - Due to the risk of failure in existing prestressed concrete bridges, the assessment of the susceptibility of prestressing steel to hydrogen‐induced stress corrosion cracking will become more important in the future. At present, the used normative ISO 15630‐3 test gives unpersuasive and diverging results using a free corrosion approach for the needed hydrogen charging for stress corrosion cracking initiation. A newly developed test method uses the cathodic polarization to control the supply of electrons for hydrogen charging instead of an uncontrolled and variable supply of electrons by metal dissolution during free corrosion. Experimental data shows a reliable differentiation between highly susceptible known quenched and tempered wires and robust cold‐drawn wires with this new test. A round robin with eight participating testing institutes demonstrated the reproducibility of results testing a cold‐drawn wire batch of St 1470/1670. In contrast to previously reported experience in the literature, the new method ranks the Cr‐alloyed quenched and tempered (“new‐type”) wires as highly‐susceptible as the “old‐type” wires without Cr‐alloy. KW - Cathodic polarization KW - Chemical composition KW - Chromium KW - Prestressing steels KW - Quenched and tempered KW - Stress corrosion cracking KW - Susceptibility KW - Wires PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639735 DO - https://doi.org/10.1002/maco.70033 SN - 0947-5117 SP - 1 EP - 10 PB - Wiley-VCH CY - Weinheim AN - OPUS4-63973 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ebell, Gino A1 - Seifert, Lando A1 - Burkert, Andreas T1 - Innovative Korrosionsprüfung für Beton- und Spannstähle T1 - Test methods for corrosion testing of reinforcing and prestressing steels N2 - Korrosion ist einer der maßgeblichen Schädigungsmechanis-men im Stahlbetonbau und limitiert die Nutzungsdauer vonInfrastrukturbauwerken zum Teil erheblich. Dabei differenziertman zwischen verschiedenen Korrosionsvarianten, Korrosioninfolge Karbonatisierung des Betons, chloridinduzierte Korro-sion an Meerwasserbauwerken oder durch Tausalzbelastungund im Fall von Spannstahlbauwerken kann zusätzlich was-serstoffinduzierte Spannungsrisskorrosion (SpRK) auftreten.Für den Einsatz alternativer Betonstähle wie nichtrostenderBetonstahl gilt es, die Höhe des kritischen korrosionsaus-lösenden Chloridgehalts zu bestimmen. Um diesen für diejeweiligen Betonstähle zu ermitteln, fehlen bislang jedochnormativ geregelte Prüfverfahren. Die Empfindlichkeit vonSpannstählen gegenüber SpRK bedarf gemäß aktueller Nor-mung Langzeit-Auslagerungstests, die eine werkseigeneProduktionskontrolle aufgrund der langen Prüfzeiten nahezuunmöglich machen. Ein neu entwickeltes Prüfverfahren unterAnwendung kathodischer Polarisation, das inzwischen imneusten Entwurf der DIN EN ISO 15630–3 aufgenommenwurde, ermöglicht eine Bewertung der SpRK-Empfindlichkeitfür Spanndrähte innerhalb von 24 Stunden. Die Ergebnissetragen zur Verbesserung der Lebensdauerabschätzung undzur Weiterentwicklung von Normen für korrosionsbeständigeBetonstähle und der Robustheitsbewertung von Spannstählenbei. N2 - Corrosion is a primary damage mechanism in reinforced concrete construction, significantly reducing the service life of infrastructure. A categorisation of corrosion is imperative for the comprehension of the subject. The corrosion of concrete can be attributed to the carbonation process, whilst chloride-induced corrosion is prevalent in structures exposed to seawater or by de-icing salt. Additionaly to the former corrosion processe, prestressing steel structures could be also highly susceptible to hydrogen-induced stress corrosion cracking (SCC). In order to utilise alternative reinforcing steels, such as stainless reinforcing steel, it is necessary to ascertain the level of critical chloride threshold that can induce corrosion. Nevertheless, there is an absence of standardised test methods for determining this for the respective reinforcing steels to date. Acc. to current standardization, the sensitivity of prestressing steels to chromium content necessitates long-term ageing tests, which impede in-house production control due to the extended testing times. However, a newly developed test method using cathodic polarization, which has now been included in the latest draft of DIN EN ISO 15630–3, makes it possible to assess the susceptibility of prestressing steels to corrosion cracking within 24 hours. The results of this study will contribute to the improvement of service life estimation and the further development of standards for corrosion-resistant reinforcing steels and the robustness assessment of prestressing steels. KW - Korrosion KW - Spannstahl KW - Nichtrostender Betonstahl KW - Corrosion KW - Prestressing steel KW - Stainless reinforcing steel KW - Wasserstoff KW - Spannungsrisskorrosion KW - Lochkorrosion KW - Hydrogen KW - Stress corrosion cracking KW - Pitting corrosion PY - 2025 DO - https://doi.org/10.1002/best.202500025 SN - 0005-9900 SN - 1437-1006 SP - 1 EP - 8 PB - Ernst CY - Berlin AN - OPUS4-63305 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ebell, Gino A1 - Burkert, Andreas A1 - Günther, Tobias A1 - Wilsch, Gerd T1 - Untersuchungen zum korrosionsauslösenden Chloridgehalt an nicht rostendem ferritischem Betonstahl in Mörtel N2 - Der maßgebliche Korrosionsschutz von nicht rostendem Stahl in Beton basiert, anders als bei unlegiertem Betonstahl, auf der Ausbildung einer Chromoxidschicht. Die Chromoxidschicht ist in alkalischem und in carbonatisiertem Beton beständig, sodass nicht rostende Stähle in einem passiven Zustand vorliegen. Die Initiierung von Lochkorrosionserscheinungen ist dagegen auch an nicht rostenden Stählen in Beton möglich. Der korrosionsauslösende Chloridgehalt ist neben dem Gehalt an Legierungselementen (insbesondere dem Chromgehalt) und der Oberflächenbeschaffenheit auch vom Konzentrationsverhältnis von OH“ zu CI“ im Elektrolyten abhängig. Daher ist prinzipiell zu erwarten, dass in karbonatisierten Betonen geringere Chloridgehalte Korrosion initiieren können als in Betonen mit höheren pH-Werten. Dies gilt in besonderem Maße für nicht rostende Betonstähle mit geringen Chromgehalten, wie z. B. Produkte aus dem Werkstoff 1.4003 (X2CrNi12) mit seiner im Vergleich zu den Standardausteniten geringen Beständigkeit. Um den kritischen korrosionsauslösenden Chloridgehalt am Beispiel eines am Markt verfügbaren ferritischen Chromstahls zu bestimmen, wurden an der Bundesanstalt für Materialforschung und -prüfung (BAM) umfangreiche Untersuchungen zu beschleunigten Korrosionsversuchen in alkalischen und karbonatisierten Mörteln durchgeführt. Mittels Laser-induced Breakdown Spectroscopy (LIBS) konnten die korrosionsauslösenden Chloridgehalte im Phasengrenzbereich Betonstahl-Mörtel ermittelt werden. KW - Korrosion KW - Betonstahl KW - Nicht rostender KW - LIBS KW - Chloridgehalt KW - Kritischer PY - 2020 DO - https://doi.org/10.1002/bate.201900077 SN - 0932-8351 VL - 97 IS - 1 SP - 21 EP - 31 PB - Ernst & Sohn CY - Berlin AN - OPUS4-50247 LA - deu 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 - 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 - Boschmann Käthler, C. A1 - Ebell, Gino A1 - Keßler, S. A1 - Schiegg, Y. A1 - Dauberschmidt, C. A1 - Angst, U. M. T1 - A comparison of methods to assess the resistance of reinforcing steel against chloride‐induced corrosion in concrete - Particular consideration of 12% chromium steel N2 - The critical chloride content Ccrit is an indicator of the corrosion resistance of reinforcing steels in concrete. In this article, several experimental methods for determining the critical chloride content Ccrit of mild and alloyed (12% Cr) steel in cementitious materials are compared. The methods used include accelerated polarization tests and tests employing more natural (unpolarized) conditions in which chloride ingress occurs by diffusion and capillary uptake. The advantages and disadvantages of the methods are discussed, in particular, against the objective of reaching a compromise between applicability to practice and feasibility in laboratory testing. KW - Chloride‐induced corrosion KW - Critical chloride content KW - Reinforced concrete KW - Testing methods PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628485 DO - https://doi.org/10.1002/maco.202112826 SN - 0947-5117 VL - 73 IS - 3 SP - 306 EP - 325 PB - Wiley-VCH CY - Weinheim AN - OPUS4-62848 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ebell, Gino A1 - Tannert, S. A1 - Lehmann, Jens A1 - Müller, H. T1 - Offshore Weathering Campaign on a North Sea Wind Farm Part One: Corrosivity Categories N2 - The aim of this study is to investigate the corrosion behavior of materials and coatings in offshore environments, with a focus on determining the corrosivity categories at different locations on wind turbines. The collaboration between the authors enabled a 3‐year weathering campaign at the Hohe See and Albatros offshore wind farms in the North Sea. Metal panels were installed on two wind turbines to assess the corrosivity of different atmospheric conditions. Preliminary results indicate significant variations in corrosivity depending on location and material used, suggesting that current standards may not fully reflect real‐world conditions. The results of the study will help to optimize material selection and corrosion protection strategies for offshore wind farms, potentially extending their lifetime and reducing operating costs. KW - Corrosion KW - Offshore KW - Wind PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628995 DO - https://doi.org/10.1002/maco.202414711 SN - 1521-4176 SP - 1 EP - 10 PB - Wiley CY - Weinheim AN - OPUS4-62899 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mayer, T. F. A1 - Dauberschmidt, C. A1 - Bruns, M. A1 - Eichler, T. A1 - Wiens, U. A1 - Mietz, Jürgen A1 - Gehlen, C. A1 - Ebell, Gino A1 - Gerhard, G. A1 - Osterminski, K. T1 - Das Instandsetzungsprinzip W-Cl N2 - Während das Instandsetzungsprinzip W bei carbonatisierungsinduzierter Korrosion seit vielen Jahren als Standardverfahren etabliert ist, wird seine Anwendbarkeit bei chloridinduzierter Korrosion (W-Cl) in der Fachwelt bis heute kontrovers diskutiert. Zwar ergeben sich aus seiner Anwendung gegenüber anderen Instandsetzungsverfahren auf den ersten Blick u. U. deutliche wirtschaftliche Vorteile, allerdings besteht bei diesem Verfahren ein deutlich höheres Risiko, dass das Instandsetzungsziel nicht erreicht wird. Im vorliegenden Beitrag werden die technischen Grundlagen des Instandsetzungsprinzips W-Cl sowie der aktuelle Kenntnisstand - sowohl für den gerissenen als auch für den ungerissenen Beton - dargestellt und baurechtliche Konsequenzen, die sich aus dem erhöhten Ausführungsrisiko ergeben, diskutiert. Korrosionsmonitoring als Element zum Nachweis des Instandsetzungserfolgs bei Anwendung des Prinzips W-Cl wird vorgestellt. Anhand von Anwendungsbeispielen werden sowohl die Risiken, die mit dem Verfahren verbunden sind, als auch das Potenzial bei erfolgreicher Anwendung veranschaulicht. KW - Korrosion KW - Instandsetzung KW - W-Cl KW - Risse PY - 2020 DO - https://doi.org/10.1002/bate.201900083 SN - 0932-8351 VL - 97 IS - 1 SP - 2 EP - 10 PB - Ernst & Sohn CY - Berlin AN - OPUS4-50246 LA - deu 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 - 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 - Schacht, Gregor A1 - Marx, Steffen A1 - Scheerer, Silke A1 - Fiedler, Max A1 - Ritter, Robert A1 - Clages, Luise A1 - Voigt, Chris A1 - Czeschka, David A1 - Ebell, Gino A1 - Marzahn, Gero T1 - Einsturz der Carolabrücke in Dresden Teil 2 T1 - Collapse of the Carola Bridge in Dresden Part 2 Investigations into the causes of the collapse and the consequences N2 - Am 11. September 2024 ereignete sich der Teileinsturz der vorgespannten Carolabrücke in Dresden ohne Vorankündigung. Im Teil 1 des Beitrags wurden Konstruktion und Bau der Brücke, die Maßnahmen zur Instandhaltung und Sanierung sowie die Problematik Spannungsrisskorrosion vorgestellt. Im vorliegenden Teil 2 werden die umfassenden Untersuchungen zur Erkundung der Einsturzursache beschrieben, der Versuch der Rekonstruktion des Einsturzvorgangs unternommen sowie erste Erkenntnisse zum weiteren Umgang mit anderen Brücken, die SpRK‐gefährdeten Stahl enthalten, dargelegt. Zudem wird auf das Monitoring eingegangen, welches zur Absicherung der verbliebenen Überbauzüge vorgesehen wurde, und ein Ausblick auf die Herausforderungen beim Rückbau gegeben. KW - Korrosion KW - Spannungsrisskorrosion KW - Wasserstoffversprödung PY - 2025 DO - https://doi.org/10.1002/best.70008 SN - 0005-9900 SP - 1 EP - 10 PB - Ernst & Sohn GmbH AN - OPUS4-64005 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Thoralf A1 - Beck, Matthias A1 - Gümmer, Klaas A1 - Tomandl, Alexander A1 - Ebell, Gino A1 - Angst, Ueli T1 - Aktueller Sachstand zum Thema Korrosionsschutz im konstruktiven Holzbau N2 - Dieser Beitrag behandelt die Anforderungen an den Korrosionsschutz metallener Verbindungsmittel im konstruktiven Holzbau. Die Wahl des Korrosionsschutzes spielt eine entscheidende Rolle für Dauerhaftigkeit und Sicherheit. Die Korrosionsbeständigkeit wird durch holzspezifische Eigenschaften, Holzfeuchte, chemische Bestandteile und atmosphärische Bedingungen beeinflusst. Daher ist eine korrosionsschutzgerechte Werkstoffauswahl unter Berücksichtigung dieser Parameter notwendig. Historisch durch Normen wie DIN 1052 und deren Weiterentwicklungen (z. B. DIN SPEC 1052-100) geprägt, definiert der zukünftige Eurocode 5 (DIN EN 1995-1-1) Mindestanforderungen an Verbindungsmittel und deren Korrosionsschutzmaßnahmen in Bezug auf die zu erwartenden Belastungen. Trotz bestehender und kommender Normen zeigen sich in der Praxis häufig Lücken und Unsicherheiten, was den Bedarf an klaren Leitlinien und praxisnahen Lösungen unterstreicht. Fortschritte in der Beschichtungstechnologie und die Entwicklung standardisierter Prüfmethoden bieten vielversprechende Ansätze und Werkzeuge zur Verbesserung der Dauerhaftigkeit. Das Dokument betont die Bedeutung normativer Anpassungen in den kommenden Eurocodes sowie die Rolle von Forschung und Innovation, um die ökologischen und technischen Potenziale des Holzbaus besser zu nutzen und dessen Einsatz in der modernen Architektur zu fördern. KW - Holzbau KW - Korrosionsschutz KW - Verbindungsmittel KW - Eurocode 5 KW - DIN SPEC 1052-100 PY - 2025 DO - https://doi.org/10.1002/bate.70036 SN - 0932-8351 SP - 1 EP - 9 PB - Ernst & Sohn GmbH CY - Berlin AN - OPUS4-64405 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stoljarova, A. A1 - Regenspurg, S. A1 - Bäßler, Ralph A1 - Mathiesen, T. A1 - Braüner Nielsen, J. T1 - Effect of lead and copper containing brine on steel materials for geothermal applications – A corrosion study N2 - Geothermal brines often contain high amounts of lead and copper ions that can precipitate as native Cu and Pb as consequence of galvanic corrosion when brines react with carbon steel materials. This contribution evaluates which materials could overcome the problem of galvanic corrosion at geothermal environment. The behavior of these materials in water containing high chloride concentration (> 100 g/L NaCl) as well as various amounts of dissolved bCl2 and/or CuCl2 was characterized by electrochemical and exposure measurements. Both methods reveal carbon steel suffers corrosion susceptibility, accompanied by Cu◦ and/or Pb◦ precipitation on the surface. Electrochemical measurements on stainless steels result in significant difference in corrosion and repassivation potentials (Ecorr = -189 mV, Erep = 70 mV), indicating a good corrosion resistance. KW - Copper KW - Lead KW - Corrosion KW - Steel KW - Geothermal energy PY - 2021 DO - https://doi.org/10.1016/j.geothermics.2020.102024 SN - 0375-6505 VL - 91 SP - NIL_75 EP - NIL_85 PB - Elsevier CY - Amsterdam AN - OPUS4-51976 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 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 - TY - JOUR A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Bettge, Dirk A1 - Buggisch, E. A1 - Schiller, Bernadette Nicole A1 - Beck, M. T1 - Corrosion Study on Wellbore Materials for the CO2 Injection Process N2 - For reliability and safety issues of injection wells, corrosion resistance of materials used needs to be determined. Herein, representative low-cost materials, including carbon steel X70/1.8977 and low alloyed steel 1.7225, were embedded in mortar to mimic the realistic casing-mortar interface. Two types of cement were investigated: (1) Dyckerhoff Variodur commercial Portland cement, representing a highly acidic resistant cement and (2) Wollastonite, which can react with CO2 and become stable under a CO2 stream due to the carbonation process. Exposure tests were performed under 10 MPa and at 333 K in artificial aquifer fluid for up to 20 weeks, revealing crevice corrosion and uniform corrosion instead of expected pitting corrosion. To clarify the role of cement, simulated pore water was made by dispersing cement powder in aquifer fluid and used as a solution to expose steels. Surface analysis, accompanied by element mapping on exposed specimens and their crosssections, was carried out to trace the chloride intrusion and corrosion process that followed. KW - Carbon capture storage KW - CCS KW - Carbon dioxide KW - Corrosion KW - Carbon steel KW - Aquifer fluid KW - Cement KW - Casing KW - Pitting PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-519774 DO - https://doi.org/10.3390/pr9010115 SN - 2227-9717 VL - 9 IS - 1 SP - 115 PB - MDPI CY - Basel AN - OPUS4-51977 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kratzig, A. A1 - Le, Quynh Hoa A1 - Bettge, Dirk A1 - Menneken, M. A1 - Bäßler, Ralph T1 - Early Stage of Corrosion Formation on Pipeline Steel X70 Under Oxyfuel Atmosphere at Low Temperature N2 - The early stage of corrosion formation on X70 pipeline steel under oxyfuel atmosphere was investigated by applying a simulated gas mixture (CO2 containing 6700 ppmv O2, 100 ppmv NO2, 70 ppmv SO2 and 50 ppmv H2O) for 15 h at 278 K and ambient pressure. Short-term tests (6 h) revealed that the corrosion starts as local spots related to grinding marks progressing by time and moisture until a closed layer was formed. Acid droplets (pH 1.5), generated in the gas atmosphere, containing a mixture of H2SO4 and HNO3, were identified as corrosion starters. After 15 h of exposure, corrosion products were mainly X-ray amorphous and only partially crystalline. In-situ energy-dispersive X-ray diffraction (EDXRD) results showed that the crystalline fractions consist primarily of water-bearing iron sulfates. Applying Raman spectroscopy, water-bearing iron nitrates were detected as subordinated phases. Supplementary long-term tests exhibited a significant increase in the crystalline fraction and formation of additional water-bearing iron sulfates. All phases of the corrosion layer were intergrown in a nanocrystalline network. In addition, numerous globular structures have been detected above the corrosion layer, which were identified as hydrated iron sulphate and hematite. As a type of corrosion, shallow pit formation was identified, and the corrosion rate was about 0.1 mma−1. In addition to in-situ EDXRD, SEM/EDS, TEM, Raman spectroscopy and interferometry were used to chemically and microstructurally analyze the corrosion products. KW - Corrosion KW - CCUS KW - In-situ ED-XRD KW - CO2 pipeline transport KW - Oxyfuel KW - Carbon steel KW - Impurities PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506303 DO - https://doi.org/10.3390/pr8040421 SN - 2227-9717 VL - 8 IS - 4 SP - 421-1 EP - 421-19 PB - MDPI CY - Basel AN - OPUS4-50630 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 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 - Valet, Svenja A1 - Bohlmann, Tatjana A1 - Ebell, Gino A1 - Burkert, Andreas T1 - pH sensitive gel pads for the visualization of anodes and cathodes on zinc N2 - Zinc and zinc alloys have many applications. Zinc corrosion takes place in the atmosphere and is assumed to follow the water drop theory (a macroelement), in which the anode is at the centre of the drop and is surrounded by a cathode. This paper is the first to use gel electrolytes made of agar to visualize anodic and cathodic areas on zinc samples in order to examine the water drop theory. For that, agar gels were added with universal pH indicators, as the anode and cathode exhibit different pH values. In this paper, different amounts of pH indicators were tested to determine whether the indicator influences the potential, the impedance, phase shift, corrosion current and potential and corrosion layer resistance. KW - Corrosion KW - Zinc KW - Gel electrolyte PY - 2026 DO - https://doi.org/10.1016/j.electacta.2026.148134 SN - 0013-4686 VL - 551 SP - 1 EP - 21 PB - Elsevier Ltd. AN - OPUS4-65308 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gerrits, Ruben A1 - Stepec, Biwen An A1 - Bäßler, Ralph A1 - Becker, Roland A1 - Dimper, Matthias A1 - Feldmann, Ines A1 - Goff, Kira L. A1 - Günster, Jens A1 - Hofmann, Andrea A1 - Hesse, René A1 - Kirstein, Sarah A1 - Klein, Ulrich A1 - Mauch, Tatjana A1 - Neumann-Schaal, Meina A1 - Özcan Sandikcioglu, Özlem A1 - Taylor, Nicole M. A1 - Schumacher, Julia A1 - Shen, Yin A1 - Strehlau, Heike A1 - Weise, Matthias A1 - Wolf, Jacqueline A1 - Yurkov, Andrey A1 - Gieg, Lisa M. A1 - Gorbushina, Anna T1 - A 30-year-old diesel tank: Fungal-dominated biofilms cause local corrosion of galvanised steel N2 - The increased use of biodiesel is expected to lead to more microbial corrosion, fouling and fuel degradation issues. In this context, we have analysed the metal, fuel and microbiology of a fouled diesel tank which had been in service for over 30 years. The fuel itself, a B7 biodiesel blend, was not degraded, and—although no free water phase was visible—contained a water content of ~60 ppm. The microbial community was dominated by the fungus Amorphotheca resinae, which formed thick, patchy biofilms on the tank bottom and walls. The tank sheets, composed of galvanised carbon steel, were locally corroded underneath the biofilms, up to a depth of a third of the sheet thickness. On the biofilm-free surfaces, Zn coatings could still be observed. Taken together, A. resinae was shown to thrive in these water-poor conditions, likely enhancing corrosion through the removal of the protective Zn coatings. KW - Fungal biofilms KW - Biodiesel degradation mechanisms PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655014 DO - https://doi.org/10.1038/s41529-025-00731-2 SN - 2397-2106 VL - 10 IS - 1 SP - 1 EP - 14 PB - Springer Science and Business Media LLC AN - OPUS4-65501 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tidblad, Johan A1 - Moya Núñez, Alice A1 - de la Fuente, Daniel A1 - Ebell, Gino A1 - Flatlandsmo Berglen, Tore A1 - Grøntoft, Terje A1 - Hans, Ulrik A1 - Christodoulakis, Ioannis A1 - Kajánek, Daniel A1 - Kreislová, Kateřina A1 - Kwiatkowski, Lech A1 - La Torreta, Teresa A1 - Lutze, Rafał A1 - Pinar Larrubia, Guadalupe A1 - Pintus, Valentina A1 - Prange, Michael A1 - Spezzano, Pasquale A1 - Varotsos, Costas A1 - Verney-Carron, Aurélie A1 - Vuorio, Tiina A1 - Yates, Tim T1 - Corrosion and Soiling in the 21st Century: Insights from ICP Materials and Impact on Cultural Heritage N2 - This paper reviews results published by the International Co-operative Programme on Effects on Materials including Historic and Cultural Monuments (ICP Materials) with emphasis on those obtained after the turn of the century. Data from ICP Materials come from two main sources. The first is through exposures of materials and collection of environmental data in a network of atmospheric exposure test sites mainly distributed across Europe. Corrosion of carbon steel has continued to decrease during the period 2000–2020 but corrosion of zinc only up until 2014, and the trend in zinc corrosion is only visible when examining four-year data. Surface recession of limestone as well as soiling of modern glass show no decreasing trend during 2000–2020. The second is through case studies performed at heritage sites across Europe. Risk analysis of corrosion and soiling for twenty-six sites indicate that currently soiling is a more significant maintenance trigger than corrosion. Costs for maintaining heritage sites are substantial and costs attributable to air pollution is estimated from 40% to as much as 80% of the total cost. Future directions of the program are work on effects of particulate matter, improving the scientific basis for the work, and making the monitoring data publicly available. KW - Corrosion KW - Atmospheric corrosion KW - Soiling PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644651 DO - https://doi.org/10.3390/cmd6040054 SN - 2624-5558 VL - 6 IS - 4 SP - 1 EP - 25 PB - MDPI AG AN - OPUS4-64465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gluth, Gregor A1 - Ebell, Gino A1 - Hlavacek, Petr A1 - Mietz, Jürgen T1 - Chloride‐induced steel corrosion in alkali‐activated fly ash mortar: Increased propensity for corrosion initiation at defects N2 - Chloride contents at the steel–mortar interface that initiate steel corrosion were determined for carbon steel in alkali‐activated fly ash mortar for three different exposure conditions: exposure to 1 M NaCl solution; leaching in deionized water and then exposure to 1 M NaCl solution; and leaching in deionized water, aging in air at 20°C and natural CO2 concentration, and then exposure to 1 M NaCl solution. For comparison, a Portland cement mortar, exposed to 1 M NaCl solution, was studied. The median values of the corrosion‐initiating chloride contents (average over the full length of the rebar) in the alkali‐activated fly ash mortar varied between 0.35 and 1.05 wt% Cl with respect to binder, consistently lower than what was obtained for the Portland cement mortar, but with no clear trend regarding the exposure conditions. For most of the alkali‐activated fly ash mortar specimens, preferential corrosion at the connection between the working electrode and the external measurement setup was observed, while preferential corrosion did not occur for the Portland cement mortar. Scanning electron microscopy and auxiliary experiments in synthetic solutions indicated that this behavior was caused by inhomogeneities at the steel–mortar interface in the alkali‐activated mortar, likely due to its peculiar rheological properties in the fresh state. KW - Alkali-activated materials KW - Steel corrosion KW - Critical chloride content KW - Steel-concrete interface PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507268 DO - https://doi.org/10.1002/maco.202011541 VL - 71 IS - 5 SP - 749 EP - 758 PB - Wiley-VCH AN - OPUS4-50726 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Karafiludis, Stephanos A1 - Standl, Jacob A1 - Ryll, Tom W. A1 - Schwab, Alexander A1 - Prinz, Carsten A1 - Wolf, Jakob B. A1 - Kruschwitz, Sabine A1 - Emmerling, Franziska A1 - Völker, Christoph A1 - Stawski, Tomasz M. T1 - High-Entropy Phosphate Synthesis: Advancements through Automation and Sequential Learning Optimization N2 - Transition metal phosphates (TMPs) are extensively explored for electrochemical and catalytical applications due to their structural versatility and chemical stability. Within this material class, novel high-entropy metal phosphates (HEMPs)─containing multiple transition metals combined into a single-phase structure─are particularly promising, as their compositional complexity can significantly enhance functional properties. However, the discovery of suitable HEMP compositions is hindered by the vast compositional design space and complex or very specific synthesis conditions. Here, we present a data-driven strategy combining automated wet-chemical synthesis with a Sequential Learning App for Materials Discovery (SLAMD) framework (Random Forest regression model) to efficiently explore and optimize HEMP compositions. Using a limited set of initial experiments, we identified multimetal compositions in a single-phase crystalline solid. The model successfully predicted a novel Co0.3Ni0.3Fe0.2Cd0.1Mn0.1 phosphate octahydrate phase, validated experimentally, demonstrating the effectiveness of the machine learning approach. This work highlights the potential of integrating automated synthesis platforms with data-driven algorithms to accelerate the discovery of high-entropy materials, offering an efficient design pathway to advanced functional materials. KW - Metal phosphates KW - High entropy KW - Sequential learning KW - Automated synthesis KW - MAP KW - Random forest KW - Machine learning PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641554 DO - https://doi.org/10.1021/acs.cgd.5c00549 SN - 1528-7483 VL - 25 IS - 19 SP - 7989 EP - 8001 PB - American Chemical Society (ACS) CY - Washington, DC AN - OPUS4-64155 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nikoonasab, Ali A1 - Müller, Thoralf A1 - Gluth, Gregor T1 - Study of steel behavior in synthetic pore solutions of GGBFS-containing cements using EIS N2 - Steel corrosion in sulfide-containing solutions presents a challenge in a number of environments and appli¬cations, such as the kraft process, the oil and gas industry, and reinforced concrete structures. In concrete, sulfides are introduced by ground granulated blast-furnace slag (GGBFS), which is a widespread component of standard cements and which can also be utilized in the production of alkali-activated materials (AAMs). However, a knowledge gap exists concerning the compositions of pore solutions in GGBFS-containing cements, especially regarding sulfur and its various species and understanding how these sulfur species affect the surface layer and the corrosion behavior of steel in such environments. The present study employed electrochemical impedance spec¬tros-copy to study the behavior of steel in synthetic solutions representing GGBFS-containing cements and AAMs. The electrochemical behavior of steel in sulfide-containing solutions differs from that observed in ordinary Portland cement solutions, generally exhibiting lower open circuit potentials and polarization resistances in the former environments. This suggests that the criteria or standards used to assess the probability of steel corrosion in Portland cement concrete are not applicable to GGBFS-containing concrete due to differences of their pore solution compositions. T2 - International Workshop on Impedance Spectroscopy – IWIS 2024 CY - Chemnitz, Germany DA - 24.09.2024 KW - Cement KW - Ground granulated blast-furnace slag KW - Sulfide KW - Steel corrosion KW - Impedance spectroscopy PY - 2024 DO - https://doi.org/10.1109/IWIS63047.2024.10847235 SP - 44 EP - 48 PB - IEEE AN - OPUS4-61221 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -