Microstructural evolution of undercooled Fe83Ga17 magnetostrictive alloys

Using electromagnetic levitation melting combining with fluxing method, the Fe83Ga17 alloys were undercooled up to 173 K through superheating–cooling cycles. The results showed that the microstructure was closely related to the undercooling. When the undercooling was lower than 53 K, the structures consisted of coarse dendrites and some dark particles in interdendrite. With the increase of undercooling, the solidified microstructures tended to be integrated, and the grain had preferred orientation. The texture of [1 0 0] orientation were developed by the undercooling process. The cooling rate of heat treatment significantly affects the microstructure of Fe83Ga17 alloys. The water-quenched process could restrain the precipitation of DO3 phase, and the low cooling rate in the process of furnace cooling could lead to form the metastable DO3 phase.