English

Towards the ab initio based theory of the phase transformations in iron and steel

Materials Science 2017-07-17 v1

Abstract

Despite of the appearance of numerous new materials, the iron based alloys and steels continue to play an essential role in modern technology. The properties of a steel are determined by its structural state (ferrite, cementite, pearlite, bainite, martensite, and their combination) that is formed under thermal treatment as a result of the shear lattice reconstruction "gamma" (fcc) -> "alpha" (bcc) and carbon diffusion redistribution. We present a review on a recent progress in the development of a quantitative theory of the phase transformations and microstructure formation in steel that is based on an ab initio parameterization of the Ginzburg-Landau free energy functional. The results of computer modeling describe the regular change of transformation scenario under cooling from ferritic (nucleation and diffusion-controlled growth of the "alpha" phase to martensitic (the shear lattice instability "gamma" -> "alpha"). It has been shown that the increase in short-range magnetic order with decreasing the temperature plays a key role in the change of transformation scenarios. Phase-field modeling in the framework of a discussed approach demonstrates the typical transformation patterns.

Keywords

Cite

@article{arxiv.1707.04287,
  title  = {Towards the ab initio based theory of the phase transformations in iron and steel},
  author = {I. K. Razumov and Yu. N. Gornostyrev and M. I. Katsnelson},
  journal= {arXiv preprint arXiv:1707.04287},
  year   = {2017}
}