A level-set formulation to simulate diffusive solid/solid phase transformation in polycrystalline metallic materials -- Application to austenite decomposition in steels

TL;DR

This paper introduces a new finite element level-set numerical framework for simulating diffusive solid-solid phase transformations in polycrystalline metals, incorporating multiple microstructural mechanisms like recrystallization.

Contribution

It presents a generalized, multi-mechanism capable numerical model for phase transformation in polycrystalline alloys, extending beyond existing methods.

Findings

Successful 1D and 2D test case simulations

Good agreement with ThermoCalc estimations

Potential for predicting complex microstructural evolutions

Abstract

Numerous full-field numerical methods exist concerning the digital description of polycrystalline materials and the modeling of their evolution during thermomechanical treatments. However, these strategies are globally dedicated to the modeling of recrystallization and grain growth for single-phase materials, or to the modeling of phase transformations without considering recrystallization and related phenomena. A generalized numerical framework capable of making predictions in a multi-phase polycrystalline context while respecting the concomitance of the different microstructural mechanisms is thus of prime interest. A novel finite element level-set based full-field numerical formulation is proposed to principally simulate diffusive solid-solid phase transformation at the mesoscopic scale in the context of two-phase metallic alloys. A global kinetic framework, capable of accounting for other concomitant mechanisms such as recrystallization and grain growth is considered in this numerical model. The proposed numerical framework is shown to be promising through a couple of illustrative 1D and 2D test cases in the context of austenite decomposition in steels and compared with ThermoCalc estimations.