Heterogeneous precipitation on dislocations: effect of the elastic field on precipitate morphology

The shape of a coherent non-misfitting FeC precipitate formed from solute atoms that interact with a dislocation stress field was studied using kinetic Monte Carlo simulation on a rigid lattice. The system studied is a model for binary alloys with an interstitial alloying element similar to Fe–C. The interaction with the dislocation comprises both a short-range chemical term and a long-range deformation field. The effect of each of these terms on precipitate shapes for different C supersaturations was investigated. A simple analytical model is proposed to rationalize the results obtained in the atomistic simulations.