Nonequilibrium effects of primary solidification on peritectic reaction and transformation in undercooled peritectic Fe–Ni alloy

Applying the glass fluxing method, a peritectic Fe–Ni alloy with a composition of Fe–4.35 at.% Ni was undercooled. It was found that when the initial melt undercooling (ΔT) is smaller than 130 K, the overall thickness of the peritectic phase formed in peritectic reaction (PR) and peritectic transformation (PT) decreases as ΔT increases. The nonequilibrium effects of the primary solidification on PR and PT in the undercooled peritectic Fe–Ni alloys were illuminated. With increasing ΔT, since the driving forces for PR and PT change slightly, the decrease of the overall thickness of the peritectic phase formed in PR and PT can be mainly ascribed to the reduced transformation time for PT.