A new model for fatigue crack growth after a single overload

Abstract

Several co-existing, mutually competitive mechanisms are involved in fatigue crack growth after overloading. The lowest fatigue crack growth rate, the crack growth increment at which the fatigue crack growth rate reaches its minimum, and the overloading affected zone size are the three most important parameters to describe an overload event. A new model for the fatigue crack growth rate based on these three parameters has been proposed to describe the fatigue crack growth behavior after a single overload. By so doing, not only can the well recognized mechanisms like crack closure and compressive residual stresses be considered, but also those mechanisms that have been less discussed before, like crack tip blunting and strain hardening.