Dynamic Analysis of Recalescence Process and Interface Growth of Eutectic Fe₈₂B₁₇Si₁ Alloy

By employing the glass fluxing technique in combination with cyclical superheating, the microstructural evolution of the undercooled Fe₈₂B₁₇Si₁ alloy in the obtained undercooling range was studied. With increase in undercooling, a transition of cooling curves was detected from one recalescence to two recalescences, followed by one recalescence. The two types of cooling curves were fitted by the break equation and the Johnson–Mehl–Avrami–Kolmogorov model. Based on the cooling curves at different undercoolings, the recalescence rate was calculated by the multi-logistic growth model and the Boettinger–Coriel–Trivedi model. Both the recalescence features and the interface growth kinetics of the eutectic Fe₈₂B₁₇Si₁ alloy were explored. The fitting results that were obtained using TEM (SAED), SEM and XRD were consistent with the changing rule of microstructures. Finally, the relationship between the microstructure and hardness was also investigated.