Direct modeling of multi-axial fatigue failure for metals

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:125

Article

Wang, Zhao-Ling^1,2  Xiao, Heng¹ 

[1] Jinan Univ, Sch Mech & Construct Engn, MOE Key Lab Disaster Forecast & Control Engn, Guangzhou 510632, Guangdong, Peoples R China

[2] Weifang Univ, Sch Math & Informat Sci, Weifang 261601, Shandong, Peoples R China

关键词: Metals;    Finite deformation;    Thermo-coupled effects;    New elastoplastic equations;    Fatigue failure;    Direct simulation;   

DOI  :  10.1016/j.ijsolstr.2017.07.003

来源: Elsevier

【 摘 要 】

Innovative elastoplastic J(2) flow models with nonlinear combined hardening are proposed for the purpose of simulating multi-axial thermo-coupled fatigue failure for metals and alloys, in a direct sense without involving any usual damage-like variables and any ad hoc failure criteria. As contrasted with usual models, the yield condition and the loading-unloading conditions need not be imposed as extrinsic coercive conditions but may be automatically incorporated into a free, smooth flow rule in a more realistic sense. Novel results in three respects are available directly from model predictions, namely, (i) complex features of thermo-coupled fatigue failure may be automatically represented by simple asymptotic properties of the hardening functions introduced, (ii) critical failure states may be derived with a criterion in unified form, and, in particular, (iii) direct procedures may be established for determining fatigue lives under either stress cycles or thermal cycles. Simulation results in the simplest cases of the proposed model are in good agreement with experimental data. (C) 2017 Elsevier Ltd. All rights reserved.

【 授权许可】

Free