Void nucleation in spheroidized carbon steels Part 2: Model

A double criterion for void nucleation at particle/matrix interfaces is proposed. It is based on a combined critical normal stress condition and critical elastic energy release requirement. The theory of nucleation of a spherical void cap of limited size incorporates the effects of grain boundaries and plastic incompatibility of the particle-grain-boundary-matrix system. The theoretical model predicts the appropriate form for the void-nucleation rate in spheroidized steels as a function of plastic strain, flow stress, stress triaxiality, particle size, and grain size in qualitative agreement with experimental observations.