Magnetostrictive Properties Of Fe-Ga Alloy

As a new type of magnetostrictive material, Fe-Ga alloys depend on their lower saturation magnetic field(8¹7kA·m^-1), higher magnetic sensitivity, lower brittleness,hot-rolled, higher tensile strength(⁵00MPa) and high permeability (¹00), show a prospective practice future. This paper focus on study of Fe_100-xGa_x(x=15, 16, 17, 18, 19, 20, 21) alloys and Fe₈₃Ga₁₇Tb_x, Fe₈₃Ga₁₇Dy_x(x=0.2, 0.4, 0.6, 0.8) alloys. All the contents are as follows:The performance of crystal structure and magnetostrictive properties of Fe100-xGax(x=15, 16, 17, 18, 19, 20, 21) alloys were studied. The results showed that casting state Fe_100-xGa_x(x=15, 16, 17, 18, 19, 20, 21) alloys was disorder bcc structure, the grains were bigger, most of the grains were around 1mm, the longest grains could achieve 2.94mm, and there were lots of sub-boundary in the grains. The best magnetostiction of casting state Fe_100-xGa_x(x=15, 16, 17, 18, 19, 20, 21) alloys was Fe₈₁Ga₁₉, it cancould achieve 129×10^-6.The effect of Tb contents on the performance of crystal structure and magnetostrictive properties of Fe₈₃Ga₁₇Tbx(x=0.2, 0.4, 0.6, 0.8) alloys were studied. Tb precipitated mostly lay in grain boundary and formed new phase, there also appeared punctate precipitated phase in grain after adding Tb in the Fe₈₃Ga₁₇ alloys. It made the Fe-Ga alloys were <100>orientation preferred, and improved the Magnetostrictive coefficient. Magnetostrictive Coefficient of Fe₈₃Ga₁₇ Tb 0.4 achieved 222×10-6.The effect of Dy contents on the performance of crystal structure and magnetostrictive properties of Fe₈₃Ga₁₇Dy_x(x=0.2, 0.4, 0.6, 0.8) alloys were studied. Dy precipitated mostly lay in grain boundary and formed new phase, there also appeared punctate precipitated phase in grain after adding Dy in the Fe₈₃Ga₁₇ alloys. It made the Fe-Ga alloys were <100> orientation preferred, and <100> orientation was the largest for magnetostiction. The adding Dy could greatly improve the alloys's magnetostiction, Magnetostrictive Coefficient of Fe₈₃Ga₁₇Dy_0.2 could achieve 300×10^-6.The Tb and Dy could remarkably improve properties of the alloys, the magnetostiction of Fe₈₃Ga₁₇ alloys adding small amount of Tb(0.2%) or Dy(0.2%) have the best magnetostiction. It maks the Fe-Ga alloys are <100> orientation preferred, improves the magnetostiction of Fe-Ga alloys.