TY - JOUR A1 - Klingelhoeffer, Hellmuth A1 - Aegerter, J. A1 - Scherm, T. A1 - Schenuit, E. A1 - Sotheran, S. A1 - Loveday, M. A1 - Bosch, P. A1 - Bloching, H. A1 - Olbricht, Jürgen A1 - McEnteggart, I. T1 - Discussion on "Analysis on the issues in ISO 6892-1 and TENSTAND WP4 report based on the data of confirm tests by 21 laboratories" JF - Journal of Testing and Evaluation N2 - The authors, Li et al., of the paper entitled “Analysis on the Issues in ISO 6892-1 and TENSTAND WP4 Report Based on Data to Confirm Tests by 21 Laboratories” (J. Test. Eval. DOI: 10.1520/JTE20150479 (online only)) have expressed views that the authors of this rebuttal believe to be based on fundamental misunderstandings and misinterpretations of the tensile testing standard ISO 6892-1:2009, ISO 6892-1:2016, and its former versions, thus leading to erroneous conclusions. This refutation is intended to clarify the understanding of ISO 6892-1 and to address the misunderstandings and the misinterpretations of the authors of the paper. The present standard ISO 6892-1:2016 has a long history dating back to the 1970s. At that time, the tensile testing procedure was standardized on the National and International scale in parallel. To understand the present standard, the knowledge of the history helps to understand the background of details of the testing procedure implemented today. The history of the tensile testing standard has been discussed extensively during the annual international standardization meeting of ISO committee TC 164 SC1 for the last few years, at which some of the authors of the Li et al. paper attended. The authors continue to disagree with facts that were agreed by the consortium of the European research project TENSTAND and by the present international experts involved in ISO TC 164 SC1. It appears that the principal objective of the authors regarding their present publication was to increase the testing speed during tensile testing. However, the international standardization community has previously declined similar proposals by some of the authors. Many arguments presented by Li et al. were thus refuted. The conclusions of their paper are misleading and the international standardization community for tensile testing refused to revise the present standard, ISO 6892-1 (2016), according the authors’ proposals. KW - Tensile testing procedure KW - ISO 6892-1 KW - TENSTAND WP4 Final Report PY - 2017 DO - https://doi.org/10.1520/JTE20160526 SN - 0090-3973 SN - 1945-7553 VL - 45 IS - 3 SP - 1105 EP - 1114 PB - ASTM International CY - West Conshohocken, PA, USA AN - OPUS4-40267 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bismarck, Marck A1 - Skrotzki, Birgit A1 - Olbricht, Jürgen T1 - Size effects in miniature specimen creep testing of P91 T2 - ECCC 2014 N2 - The use of miniaturized specimen geometries in mechanical testing allows extracting the sample material directly from critical components of power plants like e.g. headers and pipes. In this way, both the impacts of the manufacture of the component (including all shaping and tempering influences) and of the complex aging/loading/oxidation conditions during Service can be analyzed and representative mechanical properties are obtained. In the present study, example results of a comparative creep and creep rupture study on P91 tempered martensite ferritic Steel, involving Standard and miniature specimens that were all taken from one batch of material, are presented. Cylindrical creep specimens with a minimum gauge length diameter of 3 mm were used, representing the smallest recommended test geometry of ISO 204. The test results of miniature specimens exhibit all characteristic creep features of tempered martensite ferritic steels, and analysis of the stress and temperature dependence of creep results in values that correspond well to literature data for P91. However, direct comparison with large scale specimen data reveals small but systematic variations in minimum creep rates, elongations at fracture and times to rupture. In our contribution, these differences are discussed in the light of literature findings on specimen size influences in other heat resistant alloys. Size effects need to be considered for a correct interpretation of results from miniature specimen creep tests. T2 - 3rd International ECCC Conference CY - Rom, Italy DA - 05.05.2014 KW - Material PY - 2017 SN - 978-88-7484-510-1 SP - 430 EP - 435 PB - Tipography Inail CY - Milan AN - OPUS4-41239 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kingelhöffer, Hellmuth A1 - Affeldt, E. E. A1 - Bache, M. A1 - Bartsch, M. A1 - Beck, T. A1 - Christ, H. J. A1 - Fedelich, Bernard A1 - Hähner, P. A1 - Holdsworth, S. R. A1 - Lang, K.-H. A1 - McGaw, M. A1 - Olbricht, Jürgen A1 - Remy, L. A1 - Skrotzki, Birgit A1 - Stekovich, S. T1 - Editorial - Special issue: Recent developments in thermo-mechanical fatigue JF - International journal of fatigue N2 - Components in the Aerospace, Power and Automotive engineering sectors are frequently subjected to cyclic stresses induced by thermal fluctuations and mechanical loads. For the design of such components, reliable material property data are required which need to be acquired using well accepted and reproducible test procedures for thermo-mechanical fatigue (TMF) loading. There is limited availability of proven TMF data indicating there is need for further research and testing. The TMF behaviour of materials is often desired to be simulated in models which describe the cyclic stress-strain behaviour, the fatigue life and the cyclic crack growth behaviour. There is a continuous need for the development and amendment of such models. Models can be validated by using materials in industrial applications which are subjected to TMF loading. The 3rd Workshop on Thermo-Mechanical Fatigue was held on 27–29 April 2016 at BAM, Berlin, Germany. The workshop was attended by 90 attendees coming from 17 countries in the world. 38 presentations including five poster presentations were held. The following topics were covered by the workshop: – TMF of materials coated with Thermal Barrier Coatings. – Thermal Gradient Mechanical Fatigue. – TMF crack growth. – TMF + High Cycle Fatigue. – TMF Modelling and Lifetime Prediction. – TMF Properties of steels, cast iron, Al-, Mg- and Ni-alloys – Advanced TMF Testing Techniques. – Industrial Applications. A panel discussion was held regarding the present state of TMF testing standards (ISO and ASTM) and their potential for improvement. The discussion and contributions were summarized and forwarded to the standard committees. The 3rd TMF-Workshop ensured the continuation of international exchange of knowledge providing a forum to present and discuss all recent developments in the field of thermo-mechanical fatigue. The current special issue publishes eleven selected papers of the 3rd TMF-Workshop 2016. The papers were peer reviewed by a number of experts in the Thermo-Mechanical Fatigue sector. I hope you will enjoy reading papers of this special issue. T2 - 3rd International Workshop on Thermo-Mechanical Fatigue (TMF-Workshop 2016) CY - Berlin, Germany DA - 27.04.2016 KW - Fatigue damage KW - Thermo-mechanical fatigue KW - Fatigue life time KW - Life time prediction KW - TMF PY - 2017 DO - https://doi.org/10.1016/j.ijfatigue.2017.02.002 SN - 0142-1123 VL - 99 IS - 2 SP - 215 PB - Elsevier CY - Oxford AN - OPUS4-40895 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Olbricht, Jürgen A1 - Jürgens, Maria A1 - Mosquera Feijoo, Maria A1 - Roohbakhshan, Farshad A1 - Fedelich, Bernard A1 - Kranzmann, Axel A1 - Skrotzki, Birgit T1 - Interaction of thermo-mechanical fatigue, creep and cyclic oxidation in 9-12% Cr steels N2 - In recent years, the performance of heat resistant ferritic-martensitic steels under cyclic oxidation and cyclic mechanical loading has gained considerable attention. The growing contributions of renewable energy sources to electricity generation have triggered a shift from continuous (baseload) operation of conventional power plants towards cyclic or “flexible” operation, which is needed to stabilize the electric grids by balancing the highly variable renewable’s input. Compared to the impressive amount of data on isothermal oxidation/corrosion and static mechanical loading (creep) that was compiled over decades, only little and sometimes contradictory information is so far available on the reaction of these alloys to cyclic conditions. The latter may involve frequent transients or holds at intermediate temperatures, as well as shut-downs and start-ups with high temperature rates which result in cyclic mechanical loads (thermo-mechanical fatigue, TMF) and thermo-cyclic oxidation at variable temperature. Our contribution will report on recent findings obtained within the framework of a junior research group which investigates the oxidation and fatigue of the ferritic-martensitic grades P91, P92 and VM12 SHC under thermo-cyclic conditions. Cyclic oxidation tests are carried out in steam using different sample shapes (flat coupons, U-segments and rings taken from heat exchanger tubes). Special attention is paid to changes in the kinetics and the integrity and possible delamination/spalling of the oxide layers. Mechanical tests are carried out on material from real steam pipes with a focus on the softening behaviour and lifetime issues resulting from combined creep/TMF loadings. All experiments are carried out in the 300-620°C regime with temperature and load profiles that resemble typical loading scenarios in power plants and are complemented by detailed microstructural characterisation. T2 - IUTAM-Symposium Multi-scale Fatigue, Fracture & Damage of Materials in Harsh Environments CY - Galway, Ireland DA - 28.08.2017 KW - Low cycle fatigue KW - Thermo-mechanical fatigue KW - Creep-fatigue KW - Steam oxidation KW - Power plants PY - 2017 AN - OPUS4-42654 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klingelhöffer, Hellmuth A1 - Aegerter, J. A1 - Scherm, T. A1 - Schenuit, E. A1 - Sotheran, S. A1 - Loveday, M. A1 - Bosch, P. A1 - Bloching, H. A1 - Olbricht, Jürgen A1 - McEnteggart, I. T1 - Discussion on “Analysis on the issues in ISO 6892-1 and TENSTAND WP4 report based on the data of confirm tests by 21 laboratories” by H. Li, X. Zhou, J. Shen, and D. Luo. The regular article was published in journal of Testing and Evaluation, Vol. 45, No. 3, 2017, pp. 723–731, doi:10.1520/ JTE20150479. ISSN 0090-3973 JF - Journal of Testing and Evaluation N2 - The authors, Li et al., of the paper entitled “Analysis on the Issues in ISO 6892-1 and TENSTAND WP4 Report Based on Data to Confirm Tests by 21 Laboratories” (J. Test. Eval. DOI: 10.1520/JTE20150479 (online only)) have expressed views that the authors of this rebuttal believe to be based on fundamental misunderstandings and misinterpretations of the tensile testing standard ISO 6892-1:2009, ISO 6892-1:2016, and its former versions, thus leading to erroneous conclusions. This refutation is intended to clarify the understanding of ISO 6892-1 and to address the misunderstandings and the misinterpretations of the authors of the paper. The present standard ISO 6892-1:2016 has a long history dating back to the 1970s. At that time, the tensile testing procedure was standardized on the National and International scale in parallel. To understand the present standard, the knowledge of the history helps to understand the background of details of the testing procedure implemented today. The history of the tensile testing standard has been discussed extensively during the annual international standardization meeting of ISO committee TC 164 SC1 for the last few years, at which some of the authors of the Li et al. paper attended. The authors continue to disagree with facts that were agreed by the consortium of the European research project TENSTAND and by the present international experts involved in ISO TC 164 SC1. It appears that the principal objective of the authors regarding their present publication was to increase the testing speed during tensile testing. However, the international standardization community has previously declined similar proposals by some of the authors. Many Arguments presented by Li et al. were thus refuted. The conclusions of their paper are misleading and the international standardization community for tensile testing refused to revise the present standard, ISO 6892-1 (2016), according the authors’ proposals. KW - Tnsile testing KW - ISO 6892-1 KW - TENSTAND WP4 Report PY - 2017 UR - www.astm.org DO - https://doi.org/10.1520/JTE20160526 SN - 0090-3973 VL - 45 IS - 3 SP - 1105 EP - 1114 PB - ASTM CY - West Conshohocken, PA, USA AN - OPUS4-46690 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -