摘要
通过两种材料的缺口表面裂纹扩展规律的实验研究和非线性有限元的数值计算,指出只有当缺口裂纹冲出缺口的非线性应力场,由线弹性断裂力学所确定的应力强度因子成为裂纹扩展的驱动力时,Paris 公式方可用于表征缺口表面裂纹扩展速率.为工程应用需要,提出当 n′>0.2和表面裂纹长度2c>1mm 时,Paris 公式可以应用于描述缺口表面裂纹的扩展速率.
Based on both the experimental investigation of notch surface crack propagation law and the numerical procedures of nonlinear finite element for two materials,it is pointed that the Paris relationship can only be applied to representing notch surface crack propagation rate provided a notch crack crosses a nonlinear stress field and the stress intensity factor characterized in terms of linear fracture mechanics becomes a driving force.For the purpose of engineer- ing practice,on the conditions that n′>0.2 and surface crack length 2c>1 mm, a surface crack propagation rate can be characterized by the Paris relationship.
出处
《北方交通大学学报》
CSCD
北大核心
1991年第4期63-67,共5页
Journal of Northern Jiaotong University
关键词
Paris公式
表面裂纹
裂纹扩展
钢
Paris relationship
surface crack
crack growth/notch nonlinear stress field
cyclic strain hardening exponent
