The Influence of Heating Rate on Phase Transformation of ZnFe Coating in Hot Stamping

Abstract

In this study, the ZnFe coated boron steel specimens were treated by rapid heating at different heating rates from 20 °C/s to 100 °C/s. The coating morphologies and phase compositions were characterized to investigate the influence of heating rate on phase transformation of ZnFe coating. The results indicated that there was no continuous α-Fe(Zn) layer formed at coating/substrate interface during the heating-up stage when the heating rate was higher than 50 °C/s. As a result, the phase transformation of the coating was facilitated. At the heating rate of 100 °C/s, a one-layer coating structure composed of α-Fe(Zn) phase was formed within 100 s, which is significantly shortened compared to the traditional furnace heating method.