Secondary recrystallization induced by composite precipitates in magnetostrictive Fe-Ga alloy thin sheet

Abstract

Secondary recrystallization of Goss ({110} < 001>) texture is successfully produced by using nanometer-sized composite inhibitor in primary cold rolled Fe81Ga19 alloy sheet. Nanometer-sized sulfides consisting of MnS and Cu2S are dispersedly precipitated during hot rolling and normalization as inhibitors for secondary recrystallization. Strong γ texture with peak at {111} < 112> and weak Goss texture distributed through the sheet thickness in primarily annealed sheets can provide favorable environment for the secondary recrystallization. The higher onset and finishing temperatures of secondary recrystallization confirm the stronger inhibition and driving force originated from the composite inhibitors. Centimeter-sized Goss grains and large magnetostriction coefficient are obtained by primary cold rolling methods without surface energy effect. The result indicates that complete secondary recrystallization in Fe-Ga alloy can be realized by precisely controlling inhibitor characteristic and primary recrystallization texture.