Effect of applied strain on phase separation of Fe-28 at.% Cr alloy: 3D phase-field simulation

摘要

A quantitative simulation of the separation of the alpha' phase in Fe-28 at.% Cr alloy under the effects of applied strain is performed by utilizing a three-dimensional phase-field model. The elongation of the Cr-enriched alpha' phase becomes obvious with the influence of applied uniaxial strain for the phase separation transforms from spinodal decomposition of 700 K to nucleation and growth of 773 K. The applied strain shows a significant influence on the early stage phase separation, and the influence is enlarged with the elevated temperature. The steady-state coarsening with the mechanism of spinodal decomposition is substantially affected by the applied strain for low-temperature aging, while the influence is reduced as the temperature increases and as the phase separation mechanism changes to nucleation and growth. The peak value of particle size distribution decreases, and the PSD for 773 K becomes more widely influenced by the applied strain. The simulation results of separation of the Cr-enriched alpha' phase with the applied strain provide a further understanding of the strain effect on the phase separation of Fe-Cr alloys from the metastable region to spinodal regions.