Secondary Recrystallization Texture Evolution And Magnetostrictive Properties Of Fe-Ga Alloy Sheet

Fe-Ga alloy has attracted much attention due to its excellent property of high strength,good toughness,low saturation magnetic field and low cost.Fe-Ga alloy exhibits significant anisotropic in magnetostriction,and it needs to be processed into thin sheet to reduce the serious eddy current losses used in high frequency.The conventional rolling and annealing method for preparing thin sheet has been applied in Fe-Ga alloy.Strong ? fiber(<001>//RD)texture induced by secondary recrystallization can promote the magnetostriction of Fe-Ga alloys and receives much attentions.At present,micron-sized precipitates of NbC has been adopted as the inhibitor for inhibiting the normal grain growth,and the secondary recrystallized Goss grains are induced by the surface energy or other drive force by special atmosphere.However,in view of the shortcoming of the current inhibitors,it is necessary to introduce special inhibitor with effective pinning and preferential failure to promote the secondary recrystallization,and provides a simple and efficient method for preparing secondary recrystallized Fe-Ga alloy sheet.In this study,Fe-Ga alloy sheets with secondary recrystallization Goss texture were prepared by constructing system composition inhibitor.The evolution of microstructure,texture and inhibitor characteristics during rolling and annealing process were analyzed by with macro/micro characterization method to clarify the formation and development mechanism of secondary recrystallization texture in Fe-Ga alloy thin sheet.The main innovations and conclusions are as follows:(1)Based on the construction of composite inhibitor system(MnS+Cu2S),the nano-sized precipitates were obtained by compositional design,regulation of rolling and annealing parameters.The nano-sized precipitates can provide pinning for the primary grains in the early stage of annealing,and induce the formation of secondary recrystallized nucleation.Finally,the centimeter-sized Goss grain with excellent magnetostrictive properties were obtained in thin gauge Fe-Ga alloy sheet.(2)The high fraction of {111}<112>grains in primary recrystallization provides the basis for the abnormal growth of Goss grains due to the special lattice relationship.The critical grain size is calculated by the quantity and size of precipitates in the annealing process.The result shows the smaller Rm/<R>and the narrower grain size distribution below 950? can suppress the normal grain growth,while the smaller Rm/<R>and the broadens of the distribution of grain size could promote the secondary recrystallization due to Goss grain gets rid of pinning and grow preferably due to the special lattice relationship with matrix grain.(3)The inherent inhibitors(MnS+Cu2S)and the acquired nitriding inhibitor(NbN)are obtained by compositional design,regulation of rolling and annealing parameters,the Fe-Ga alloy sheet with strong Goss texture and excellent magnetostriction property is prepared by first-stage cold rolling method.(4)This study proposes a simple and efficient preparation method of Fe-Ga alloy sheet with secondary recrystallization Goss texture.The magnetostrictive property of the Fe-Ga alloy sheet should be further improved through the optimization of choice of inhibitor system and the regulation of rolling and annealing process.