Grain-boundary nucleation in deformation-induced martensitic transformation: In-situ TEM observation vs. MD simulation

Abstract

Deformation-induced martensitic transformation (DIMT) can achieve both high strength and high ductility in steel materials, but the nucleation mechanism has not been clarified yet. In this study, an atomic model of the crystal orientation of materials in which DIMT was observed by in-situ transmission electron microscopy (TEM) was created and analyzed by molecular dynamics simulation to investigate the generality of the obtained dominant factors of nucleation in our previous molecular dynamics (MD) studies. As a result, it was confirmed that the nucleation sites obtained by MD simulation generally corresponded to those observed in in-situ TEM. It was also confirmed that the transformation strain is an important dominant factor in variant selection, which is consistent with the results of the previous MD studies.