Effects of Second Phase Particle Dispersion on Kinetics of Isothermal Peritectic Transformation in Fe–C Alloy

Effects of dispersion of insolvable particles on peritectic transformation kinetics in Fe–C binary alloy system have been investigated by means of a model experiment based on a diffusion couple method. During isothermal holding of the diffusion couple of δ and liquid phase samples, the peritectic transformation proceeds by migrations of ferrite(δ)/austenite(γ) interface and liquid(L)/γ interface. It was observed that the existence of insolvable particle, ZrO2, in δ phase retarded the migration of δ/γ interface and also the migration of L/γ interface. The retarding effect by the ZrO2 particles becomes strong as volume fraction of particles increases and/or particle radius decreases, which is qualitatively coincident with the effect of particles on grain growth (Zener pinning). These findings were verified by multi-phase field simulations