Multivariant microstructure evolution in Ti-alloys: insights from a quantitative phase-field study

In the present work, we employ a CALPHAD-integrated physics-based quantitative multi-phase field model to study the microstructure evolution in a multi-phase Ti-alloy. In this model we use the free energies obtained from TTTI3 thermodynamic database for Ti-based alloys using a CALPHAD approach. For numerical implementation of the model, we solve the governing equations in their weak form using the open-source MOOSE finite element framework. Our model is successfully able to capture all the possible orientational variants in Ti- alloy system. Moreover, we elucidate the complex interaction between the variants using two- and multi-particle simulations. We show that the elastic energies associated with the variants play significant role in their growth behavior. We also explore the effect of anisotropy in interfacial energy on the variant evolution.

Automated summary

In this work, we utilize a CALPHAD-integrated physics-based quantitative multi-phase field model to investigate the microstructure evolution in a multi-phase Ti-alloy. By employing the free energies from TTTI3 thermodynamic database, we successfully capture all the possible orientational variants in the Ti-alloy system. Additionally, through two- and multi-particle simulations, we elucidate the complex interaction between the variants and demonstrate that the elastic energies associated with the variants significantly influence their growth behavior. We also explore the effect of anisotropy in interfacial energy on the variant evolution.