文献类型：期刊文献

英文题名：Ratchetting behavior of advanced 9-12% chromium ferrite steel under creep-fatigue loadings

作者：Zhao, Peng[1];Xuan, Fu-Zhen[1]

机构：[1]E China Univ Sci & Technol, Key Lab Pressure Syst & Safety, MOE, Sch Mech Engn, Shanghai 200237, Peoples R China

年份：2011

卷号：43

期号：6

起止页码：299

外文期刊名：MECHANICS OF MATERIALS

收录：;EI(收录号：20112013980533);WOS:【SCI-EXPANDED(收录号:WOS:000291834000002)】；

基金：This work was financially supported by National Natural Science Foundations of China (50835003, 10972078 and 51005076) and Natural Science Foundation of Shanghai (09JC1404400).

语种：英文

外文关键词：Ratchetting; Creep-fatigue loading; Internal stress

摘要：The ratchetting behavior of advanced 9-12% chromium ferrite steel was investigated by cyclic loading tests with various hold times and stress ratios at elevated temperature of 873 K. Particular attention was paid to the effect of hold time on the whole-life ratchetting deformation and failure mechanism. Results indicate that the total ratchetting strains under creep-fatigue loading can be decomposed into two parts, i.e., cyclic accumulated creep strain produced during the peak stress hold time (epsilon(R1)), cyclic accumulated inelastic strain produced during the stress change process (epsilon(R2)). A transition in ratchetting components and rupture behavior with the increase of hold time was observed. In the long hold time domain, a quick shakedown of ratchetting strain epsilon(R2) occurs after the very first few cycles and the rupture behavior is fully controlled by the time-dependent creep damage. In the short hold time domain, ratchetting strain epsilon(R2) increases till the specimens fails and a mixed damage mode is responsible for the failure. An attempt is made to explain the existence of these two domains in terms of the evolutions of three internal stress components (back stress, isotropic stress and viscous stress) measured at the end of the holding period. (C) 2011 Elsevier Ltd. All rights reserved.