文献类型：期刊文献

英文题名：Multi-axial creep-fatigue life prediction considering history-dependent damage evolution: A new numerical procedure and experimental validation

作者：Wang, Run-Zi[1];Guo, Su-Juan[1];Chen, Haofeng[2];Wen, Jian-Feng[1];Zhang, Xian-Cheng[1];Tu, Shan-Tung[1]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Minist Educ, Key Lab Pressure Syst & Safety, Meilong Rd 130, Shanghai 200237, Peoples R China;[2]Univ Strathclyde, Dept Mech & Aerosp Engn, Glasgow G1 1XJ, Lanark, Scotland

年份：2019

卷号：131

起止页码：313

外文期刊名：JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS

收录：;EI(收录号：20192907208818);WOS:【SCI-EXPANDED(收录号:WOS:000482247400019)】；

基金：The authors would like to acknowledge gratefully for the financial support through National Natural Science Foundation of China (51725503, 11872181, 51828501) and the 111 project. The author X.C. Zhang is also grateful for the support by Shanghai Technology Innovation Program of SHEITC (CXY-2015-001), Fok Ying Tung Education Foundation, and Young Program of Yangtze River Scholars. The author S.J. Guo is also grateful for the Shanghai Natural Science Foundation (18ZR1408900).

语种：英文

外文关键词：Creep-fatigue; Unified viscoplastic model; Life prediction; Crack initiation sites; Multi-axial stress states

摘要：In this paper, a new numerical procedure based on a cycle-by-cycle analysis has been constructed for creep-fatigue behavior and life prediction of high-temperature structures under multi-axial stress states. Within this framework, a modified unified viscoplastic constitutive model with isotropic hardening and modified kinematic hardening rules is developed to simulate the cycle-by-cycle stress-strain responses. Moreover, the newly constructed creep-fatigue approach calculates fatigue and creep damage variables using the critical plane method (CPM) and the modified strain energy density exhaustion (SEDE) model, respectively. The multi-axial ductility factor and elastic follow-up factor are also introduced into the modified SEDE model to accommodate the special multi-axial and mixed controlled modes, which are widely existed in practical structures. In order to validate the feasibility of the proposed numerical procedure, a series of creep-fatigue tests of notched specimens made from nickel-based GH4169 superalloy were carried out at 650 degrees C. The predicted numbers of cycles to crack initiation agree well with the experimental data. Evidence of crack initiation under various loading conditions was observed via the electron backscatter diffraction (EBSD) technique, indicating location-dependent crack initiations depending on loading conditions. In detail, the crack initiation sites shifting from surface to subsurface with increasing hold times can be well simulated by the proposed numerical procedure due to a reasonable description of the creep-fatigue damage evolution. (C) 2019 Published by Elsevier Ltd.