基于CTOAc评估结构断裂特性的方法研究

摘要

A method to assess the ductile fracture of damaged structure based on the crack tip opening angle (CTOA) is introduced. CTOA criterion is introduced to evaluate crack stable growth and instability during the fracture process. This paper also gives a brief introduce on the experimental way to obtain CTOAc,especially quasi- static method. The FEM on two typical M(T) specimens simulate the crack growth process and obtain the value of CTOA on each crack growth. The conclusion from the FEM is that CTOA is an important parameter to simulate ductile fracture and CTOA criterion has wild applicability and broad prospects on the high ductile material used in aerometal structure.%介绍了一种基于临界裂纹尖端张开角(CTOAc)评估破损结构延性断裂特性的方法.引入了评估裂纹稳态扩展和止裂的CTOA准则,介绍了CTOAc的试验测定方法,重点推荐准静态的方法.通过对两类典型M(T)试件进行有限元分析,应用应力失效准则及节点力释放技术模拟了结构的裂纹扩展过程,得到了对应裂纹长度的CTOA值.结果表明,CTOA是模拟延性断裂的一个重要表征参数,CTOA准则在高韧性的航空铝合金结构中具有广泛的适用性和广阔的应用前景.