Evaluation of Ordering Mobility from Antiphase Boundary Mobility in Fe3Al Using Phase-field Simulation

Determination of the mobilities for ordering transformation in Fe3Al has been attempted by comparing the rates of experimentally observed antiphase boundary (APB) migration with that simulated by a phase filed method (PFM). The simulated boundary mobility of D03-APB was sensitive to the ordering mobility. This allowed us to determine the ordering mobility for D03-LRO at 673 K to be 3 × 10–11 m3·J–1·s–1. However, the simulated boundary mobility of B2-APB was insensitive to the value of ordering mobility, and therefore the ordering mobility for B2-LRO could not be determined. The difference is ascribed to solute-drag which was quite significant at B2-APB.