Crystallographic Textures In Rolled And Recrystallized Fe₈₁Ga₁₉ Sheet

Fe-Ga alloy is an advanced and developing material with excellent mechanical, magnetostrictive properties, environmental adaptability and economical application in recent years. Comparied with giant magnetostrictive Tb-Dy-Fe alloy (Terfenol-D), Fe-Ga alloy has outstanding advantages:(1) a lower saturation magnetic field (8～17kAm-1);(2) solid solution structure with good workability;(3) higher tensile strength (～500MPa) with complex pre-stressed structure unnecessary;(4) higher permeability (～100) with good thermal stability in a wide temperature range;(5)1/3times lower in price than Terfenol-D.Fe-Ga alloy has the significant magnetic anisotropy with the largest magnetostriction coefficient along<100> direction. Because of high cost for single crystal preparation, it is necessary to develop low-cost method for<100>-textured polycrystalline Fe-Ga alloy. Moreover, high electrical conductivity leads to a serious high-frequency eddy current loss, thus the thin Fe-Ga sheet is expected in order to reduce the eddy current loss.In this study, Fe81Ga19alloy sheet was preparaed by common rolling methods. Based on solving the cold formability, the research was focused on cold rolling and primary recrystallization textures to establish an important foundation for the development of high grade Fe-Ga alloy sheet.Cold rolling texture shows significant texture gradient, the near surface is dominated by Goss ({110}<001>), whereas inner of sheet is characteristic of strong y fiber (<111>//ND) with peak at{111}<110> and weak a fiber (<110>//RD). With the cold rolling reduction increasing from50%to85%, shear textures in the surface and1/4layers are weakened, while a and y fibers through thickness are enhanced. Shear strain plays a dominant role near surface layer especially under lower reduction, whereas plane strain becomes dominated in most part of sheet with1/8layer is the transition layer.Primary recrystallization texture consists mainly of Goss ({110}<001>) and y fiber, Goss, however, dominates the recrystallization texture over y fiber even after considerable grain growth. The development of strong Goss through thickness can be attributed to the high density of shear bands with appropriate intensity and the enhanced cold rolling y fiber owing to the designed hot band grain size, cold rolling reduction and temperature.Thus, the present results provide a prospective route to efficiently optimize the recrystallization texture of Fe-Ga alloy.