A geometric approach to stochastically modeling fatigue crack propagationat the microstructural length scale

摘要

In the high cycle fatigue regime, determination of a structural component's life is inherently a multiscale problem. The majority of fatigue life in this regime is governed by crack nucleation and propagation processes at the microstructural length scale [1,2]. A crack governed by these processes is defined herein as being a microstructurally small fatigue crack (MSFC). However, other length scales within a component, such as the region over which all possible fatigue life limiting cracks can exist, are often microstructurally large, i.e. significantly larger than the inherent length scales of the microstructure. Thus, an efficient and accurate approach to determine numerically the high cycle fatigue life of a structure is one that uses a multiscale simulation technique.