Enhanced magnetostriction of Fe81Ga19 by approaching an instable phase boundary

There is an instable phase boundary (IPB) between A2 and (A2 + L12) in the equilibrium Fe-Ga phase diagram (a). Quenching Fe81Ga19 near the IPB (773 K) produces A2 single-phase with softening lattice, exhibiting larger magnetostriction than that of the high temperature quenched one, which is a phase mixture of A2 and D03 (b).287