Numerical simulation of tearing–fatigue interactions in 316l(N) austenitic stainless steel
- 作者：A.H. Sherry and M.A. Wilkes
- 关键词：Stainless steel ; Ductile tearing ; Fatigue ; Tearing– ; fatigue ; R6 ; Gurson model
- 刊名：The International Journal of Pressure Vessels and Piping
- 出版年：2005
- 期刊代码：89_03080161
- 类别：et
- 出版时间：2005
- 卷：82
- 期：12
- 页码：905-916
- 文件大小：584 K
摘要
The loading history of engineering components can influence the behaviour of defects in service. This paper presents, the results of a numerical study aimed at using the Gurson ductile damage model, calibrated against J R-curve data, to simulate load-history effects on ductile tearing behaviour in austenitic materials. The work has demonstrated that ductile crack growth resistance is influenced by sub-critical crack growth by an intervening mechanism such as fatigue. Fatigue crack growth under a positive R-ratio leads to increase in subsequent tearing resistance through three main mechanisms: (i) re-sharpening of the crack tip; (ii) crack extension through the fracture process zone; and (iii) cyclic loading effects on void development. The ratio of minimum to maximum stress during fatigue loading (R-ratio) has been shown to influence subsequent tearing resistance, with an R-ratio of 0.2 generally leading to a greater enhancement in tearing resistance than an R-ratio of 0.1. This behaviour is due to the influence of R-ratio on void development ahead of the fatigue crack tip. Finally, relevant experimental data compare favourably with the predicted J R-curves.