疲劳破坏主裂纹的分形分析

Fracture Analysis of Fatigue Crack Propagation

通过实验分析得到的在不同应力循环次数下疲劳破坏试件的主裂纹.发现形成疲劳破坏断口的主裂纹随着应力循环次数的增加,主裂纹形成、发展并具有分形行为;当循环次数增加到一定值时,主裂纹的分形维数随着循环次数增加而减小;当发生疲劳破坏时,主裂纹的分维数近似等于 1,对应的应力循环次数是灾变点.

Main crack of fatigue sample under different stress cycles is analyzed.The principal experimentu results show that with the increase in stress cycles,the crack ferms and develops with fractal characteristics.When the stress cycles are increased to certain value,the fractal dimension decreases with the increasing number of cycles;when fatigue fracture occurs,fractal dimension of the main crack approximates one,and the corresponding number of cycles is the catastrophe point.