Elucidation of mechanism of stress corrosion cracking and guidelines for lifetime estimation of structural materials

提出了考虑塑性变形的弹塑性断裂力学参数来研究应力腐蚀裂纹扩展。应力腐蚀裂纹扩展受塑性变形面积的影响。即在施加应力强度因子相同的情况下，大规模屈服条件下的裂纹扩展速率高于小规模屈服条件下的裂纹扩展速率。用J积分定义的等效应力强度因子是评价裂纹扩展速率的合适参数。

The elastic-plastic fracture mechanics parameter taking account of plastic deformation was proposed to investigate crack growth by stress corrosion cracking. The stress corrosion crack growth was affected by plastically deformed area. That is, the crack growth rate under the large scale yielding condition is higher than under the small scale yielding condition when applied stress intensity factor is same level. The appropriate parameter to evaluate the crack growth rate is equivalent stress intensity factor defined by J integral.