摘要
本文实验测试了预应变对20g钢断裂韧性的影响.在弹塑性有限元数值分析的基础上,讨论了裂纹尖端张开位移与最大应变间的关系及预应变量ε_p对临界断裂应变的影响.同时,在Rice-Tracey空穴扩张模型的基础上,探讨了裂纹前方空穴形成的原因及主裂纹扩展的条件,分析了预应变量ε_p对20g钢断裂性质的影响.
The effects of pre-strain on the fracture toughness have been measured experimentally. It is found that the fracture toughness of type 20g steel decreases by over 30 percent at ep= 1% as compared with that of unprestr-ained steel of the same type. At ep = 2%, however, the toughuess improves and gradually decreases again as ep increases and the fracture properties change from ductile to brittle with increased ep. Based on an elastic-plastic FEM analysis, the relationship between the crack tip opening displacement and the maximum strain have been examined. The cause of void formation in front of the crack tip, the condition for the principal crack propagation and the effects of prestrain on the fracture properties of type 20g steel are investigated with a Rice-Tracey's void growth model.
出处
《华中理工大学学报》
CSCD
北大核心
1992年第6期145-150,共6页
Journal of Huazhong University of Science and Technology
关键词
断裂韧性
断裂应变
裂纹扩展
钢
steel plate
prestrain, fracture toughness
fracture strain
void growth
crack propagation
