A review of the numerical estimation of crack closure and fatigue crack growth

This paper presents a review of the numerical methods for estimation of fat igue crack growth based on plasticity-induced fatigue crack closure under c yclic loading. Load interaction effects and temperature exposure on closure levels are highlighted. With the advent of large and fast computing power, it is possible to adopt numerical methods such as elastic-plastic finite e lement analysis to study these effects under the general class of problems dealing with variable amplitude loading. The results of numerical analysis were validated by comparison with fractographic data obtained from a series of specially designed experiments. The load interaction effects on crack c losure levels are numerically simulated and compared with the earlier exper imental results reported in literature. The effects of temperature exposure are explained using a model involving creep effects.