文献类型：期刊文献

英文题名：Cyclic softening behaviors of modified 9-12%Cr steel under different loading modes: Role of loading levels

作者：Zhao, Peng;Xuan, Fu-Zhen[1];Wu, De-Long

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

年份：2017

卷号：131

起止页码：278

外文期刊名：INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES

收录：;EI(收录号：20172803935700);WOS:【SCI-EXPANDED(收录号:WOS:000412960000025)】；

基金：The authors are grateful for the supports provided by National Natural Science Foundation of China (51325504, 51475168).

语种：英文

外文关键词：Fatigue; Ferritic steels; Internal stresses; Dislocation structure; Loading mode

摘要：Cyclic softening behavior of modified 9-12%Cr steel was investigated at 873 K under different loading modes and stress levels. Results indicated that two domains were identified depending on the plastic strain level, in which cyclic deformations and control modes were different. Significant different cyclic softening was only observed in the macroplasticity domain at high loading levels between stress and strain controlled fatigue, companied with a relatively homogenous coarsening of subgrain. By contrast, in the microplasticity domain at low loading levels, slight cyclic softening was attributed to the fact that back stress remained a relative stable value (or decreased very slightly). An additional back stress component was produced due to the heterogeneous subgrain coarsening at the inter-packet scale. As a result, the cyclic softening was retarded due to the competition between the hardening of inter-packet back stress and the softening of intragranular back stress. (C) 2017 Elsevier Ltd. All rights reserved.