Phase field study of lath martensite deformation
Phys. Rev. B 113, 104103 – Published 13 March, 2026
DOI: https://doi.org/10.1103/fwjk-tcxz
Abstract
A phase field simulation framework is used to study the martensitic microstructure and mechanical behavior of lath martensite. The model takes into account all 24 martensite variants of steel and also considers the hierarchical microstructure at the level of packets and blocks. Elastic and plastic effects are incorporated into the model. Particular emphasis is given to understand the effect of plasticity associated with martensite variant interfaces. A model parameter that can control the yielding behavior of the interfaces is introduced. It is shown that the extent of interfacial yielding can significantly influence the observed martensite morphology. The evolution of the lath martensite microstructure under loading is also simulated for different interfacial yielding conditions. It is shown that, in principle, there are two mechanisms by which the applied load can be accommodated. The first is the plastic deformation associated with the variant interfaces and the second is the growth/shrinkage of favored/unfavored variants. It is shown that these are competing mechanisms. When the interfacial plasticity is significant, the variant growth/shrinkage mechanism is suppressed.
