| Fe-Ga alloy is a magnetostrictive material with large saturation magnetostriction which is being developed around the world in recent years. Fe-Ga alloy is attracting attention increasingly by researchers for its advantages than widely used Tb-Dy-Fe alloy such as lower saturation magnetic field, easier machining deformation, better workability, higher tensile strength, higher permeability with good thermal stability in a wide temperature range and1/3times lower in price. Magnetostriction of the Fe-Ga alloy will be enhanced after adding Tb element. But as solid solubility of Tb element is seldom, the key to improve the alloy magnetostrictive properties is to add the appropriate amount of Tb.Fe-Ga alloy has the significant magnetic anisotropy with the largest magnetostriction coefficient along<100> direction. Because of high cost for single crystal and directional solidification preparation, and taking into account the high electrical conductivity of Fe-Ga alloy, the most effective way is to rolled into the thin sheet. So the keys to Manufacturing Fe-Ga-Tb alloy with excellent magnetostrictive properties are to achieve stable shape and control the η(<100>//RD) texture.The paper studies the phase structure, magnetostriction and some other magnetic properties of the Fe81Ga19alloy after adding Tb element, then the alloy with0.1at.%Tb that has significant magnetostriction properties and good formability is rolled to Fe-Ga-Tb alloy sheet. The study is focus on affect of the normalization grain size to cold-rolled and primary recrystallization texture of Fe-Ga-Tb alloy.Adding Tb element to Fe81Ga19alloy does not change the phase structure of the matrix which is still bcc structure of disordered a-Fe, but do improves the magnetostrictive properties of the alloy obviously. Although the magnetostrictive coefficient is not a linear increase as increasing of Tb content, there is maximum of251ppm when Tb content comes to 0.15at%. That is much higher than magnetostriction coefficient of163ppm when Tb content is0. The dynamic magnetostriction coefficient improves with adding of the appropriate amount of Tb, and this can greatly improve the sensitivity of the device and the practical applicationThe cold-rolled texture of Fe-Ga-Tb alloy sheet includes mainly a texture (RD//<110>) with peak of{001}<110>, y texture and Goss texture. Size of recrystallization Goss-oriented grains in Fe-Ga-Tb alloy sheet with normalization grain size of173μm is smaller than that with normalization grain size of75μm, but the amount is dominant. It is the reason that the recrystallization Goss texture remaines a dominant position and stayes stable in the initial crystallization process and the subsequent primary growth process. We attribute this phenomenon to the appropriate shear band density and intensity formed from former hot and cold rolling reduction ratio and temperature, which provides a large number of nucleation sites, and make the Goss texture be able to maintain superiority until the grain size recrystallization to50μm.The phenomenon of Goss texture of initial crystallization in Fe-Ga-Tb alloy sheet with normalization grain size of173μm remains stable pointes out a feasible way to rationally optimize of Fe-Ga-Tb alloy recrystallization texture. |
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