Exploring the mechanism of solid-state transformation s / g during homogenization in 7Mo super austenitic stainless steel

Topologically close-packed phases (TCP phase), with ordered dense-stacked structure, realize the atomic diffusion at high temperatures by forming the defects. In this study, we investigated the a / y transformation process at high temperature in cast 7Mo super austenitic stainless steel. Based on in-situ observation and microstructure analysis, it denoted that the modulated structure appeared in a phase during the transformation process, which caused by the limited mobility of atoms. With extending homogenization time, the new y phase formed at the boundaries of the modulated structure in a phase. The size of the a phase gradually decreased as new y phase grew up. This discovery enriches the phase transformation mechanism of intermetallic compounds and provides a new sight for applying a phase at high temperature. & COPY; 2023 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).