| Abstract Scope |
Lath martensite is a characteristic structure in quenched steels with a low or negligible carbon content, maraging steels and interstitial free steels. The transformation of a parent austenite grain into lath martensite was characterized as a grain subdivision on different length scales. On a coarse scale, the austenite grain breaks down to several packets, each containing extended parallel blocks. Each block is further subdivided by laths, which are narrow units with a width in the submicrometer range. In this study, we analyze the origin of lath martensite formation by using volume-conserving multi-phase field model with micro-elasticity. Although various deformation mechanisms such as Bain, Kurdjumov–Sachs, Nishiyama-Wassermann and Pitch mechanisms have been proposed for cubic to tetragonal martensitic transformation, only Bain deformation mechanism has been considered in previous phase field models. In this study, we consider all the formation mechanisms and reveal a plausible origin for the microstructure of lath martensite. |