通过调控冷轧压下率,在退火后获得3种不同的Fe₈₁Ga₁₉二元合金初次再结晶状态,采用XRD和EBSD宏微观织构分析技术研究了初次再结晶状态对高温退火后晶粒尺寸及织构的影响。结果表明：初次再结晶阶段形成更多的大尺寸η (<001>//RD)取向晶粒,有利于后续高温退火过程中的η取向晶粒择优长大甚至发生异常长大,最终在晶粒尺寸相对较小的再结晶组织中获得强η织构,饱和磁致伸缩系数可达到220×10^-6。

Fe-Ga alloys are attractive magnetostrictive materials due to large magnetostriction along <100> direction and high mechanical strength. However, sharp Goss ({110}<001>) texture and large magnetostriction coefficients were conventionally achieved by secondary recrystallization with centimeter-sized grains under the effects of inhibitor and surface energy, resulting in deteriorated mechanical properties. Texture optimization in relatively fine grained microstructure is an effective way to obtain excellent comprehensive properties. Cold rolling process can determine the difference in number and size of primary recrystallization grains among various texture components, and further influence the texture and grain size evolution during subsequent high temperature annealing. The present work aims to produce strong η texture (<001>//RD, rolling direction) in binary Fe-Ga sheet with relatively fine recrystallization grains by cold rolling parameter modification. Macro- and micro-texture analysis was applied to investigate the effects of primary recrystallization states on texture and grain size evolution during high temperature annealing in binary Fe-Ga sheet. The η grains can gain more numbers and relatively larger sizes in primary recrystallization stage, and preferably grow even abnormally during high temperature annealing. A sharp η texture and large magnetostriction coefficient are successfully developed in primarily and secondarily recrystallized sheets with relatively fine grains. The results provide a prospective route for the efficient recrystallization texture and grain size optimization in binary Fe-Ga and other bcc alloys.