摘要
用垂直剖面法测量了一种含氢高强度钢在静弯矩作用下由裂纹慢扩展形成的断裂表面不同部位的分维 D,发现 D 随断裂表面塑性成分的增加而增加。在平面应变条件下,裂纹慢扩展形成断裂表面的过程是一个增维过程,当分维达到某一临界值时,裂纹失稳扩展。
Fractal dimension of different parts of a fracture surface formed by slowcrack propagation induced by the combining effect of hydrogen and static bending momentwere determined by using the method of fracture profile analysis.The results show that thefractal dimension increases with increasing transgranular fracture which increases as thecrack propagates.This means that the increase of the fractal dimension responds to the in-crease of the energy needed to form the fracture surface and the process of forming a frac-ture surface by slow crack propagation is the one of increasing fractal dimension of thefracture surface;when the fractal dimension reaches a critical value,the crack propagationbecomes unstable.
基金
国家自然科学基金
5880056
关键词
氢
裂纹
高强度钢
断裂
分维
fractal dimension
fracture surface
process of increasing dimension
