Unraveling elastochemical effects in microstructural evolution of Al–Cu–Ni system through DFT-informed multi-phase field simulations

Abstract

Through the multi-phase field method, this research explores microstructure evolution within the Al–Cu–Ni system comprising Al-rich FCC, Al2Cu, and Al3Ni intermetallic compounds (IMCs). Notably, the Al3Ni exhibits substantial growth due to its higher free energy magnitude, while the Al2Cu phase diminishes within the FCC matrix. Additionally, this study investigates the impact of heterogeneous elastic effects on these microstructural changes. Density functional theory calculations were employed to determine temperature-dependent elastic tensor at a simulation temperature of 723 K. Initially both cases, simulations with elastic constants at 0 K and 723 K, start with identical grain areas. But by 21.45 ms, deviations notably intensify to 18.18% for single grains, underlining the importance of temperature-calibrated elastic tensor in the phase evolution driven by elastochemical effects.