文献类型：期刊文献

英文题名：Interpreting load ratio dependence of near-threshold fatigue crack growth by a new crack closure model

作者：Zhu, Ming-Liang[1];Xuan, Fu-Zhen[1];Tu, Shan-Tung[1]

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

年份：2013

卷号：110

起止页码：9

外文期刊名：INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING

收录：;EI(收录号：20133916773751);WOS:【SCI-EXPANDED(收录号:WOS:000325595100003)】；

基金：The authors are grateful for the supports provided by National Natural Science Foundation of China (51205131) and the Natural Science Foundation of Shanghai (12ZR1442900).

语种：英文

外文关键词：Fatigue crack growth; Crack closure; Near-threshold fatigue; Load ratio; Crack driving force

摘要：It was still short of generalized fatigue crack growth (FCG) models in the near-threshold regime due to its complex influencing factors. The near-threshold FCG behaviour of a rotor steel 25Cr2Ni2MoV at different load ratios was investigated experimentally, and the FCG driving mechanism was theoretically analysed based on equivalent driving force model. It was found that the crack growth process was determined by combined effects of equivalent driving force at constant amplitude loading and crack closure. A new crack closure model was proposed by considering the influences of load ratio and FCG rate, which could successfully interpret the effect of load ratio on FCG. The correlation of the crack closure model with the transition of driving forces in crack advance was beneficial to unify crack closure theory and crack growth driving parameters in the near-threshold regime. (C) 2013 Elsevier Ltd. All rights reserved.