Bauschinger effect of alloys and plasticity-induced crack closure: a finite element analysis

The effect of overloads, underloads and stress ratio on plasticity-induced crack opening level is examined for different 'model' materials. This study is focused on the consequences of the Bauschinger effect on the crack open ing level. Various finite element analyses were conducted using ABAQUS to t est these effects, involving the Chaboche constitutive equations that take into account both the Bauschinger effect of the material and its cyclic har dening or softening. The cyclic plastic behaviour of the material is found to strongly affect the crack behaviour after an overload or an underload. T he experimental data obtained on a 0.4% carbon mild steel confirm the numer ical results.