【摘要】 采用区熔定向凝固方法制备了<110>取向的Tb0.3Dy0.7(Fe1-xAlx)2(x=0,0.05,0.10,0.15)超磁致伸缩合金,在真空管式炉氩气保护条件下,对合金进行930℃×2 h的热处理,研究了热处理对于不同含量Al元素替代合金的微观组织、磁致伸缩性能和力学性能的影响。结果表明:热处理不改变Tb0.3Dy0.7(Fe1-xAlx)2合金样品定向凝固形成的<110>轴向择优取向,热处理后的合金棒样品依然保持MgCu2型立方Laves相和部分稀土相结构,没有新相对应的衍射峰产生。热处理后Tb0.3 Dy0.7(Fe1-xAlx)2合金的片层组织退化,随着Al元素含量的增加,基体内的析出相形态和分布不断发生变化。当Al的添加量为x=0.05和x=0.15时,热处理后合金的磁致伸缩性能下降,饱和磁致伸缩分别为817×10-6,571×10-6。Al的添加量x=0.10时,热处理在不降低合金饱和磁致伸缩的同时可以显著提高其压缩强度及低场动态响应。更多还原

【Abstract】 < 110 > orient-ed Tb0.3 Dy0.7(Fe1-x Alx) 2(x = 0,0.05,0.10,0.15) alloy was prepared by the method of zone-melting directional solidification and then annealed at 930 ℃ for 2 h.The effect of heat treatment on microstructure,magnetostriction and mechanical properties of the Tb0.3 Dy0.7(Fe1-x Alx) 2 alloy was investigated.The results show that the primary phases of Tb0.3 Dy0.7(Fe1-x Alx) 2 alloy are the MgCu2-type cubic laves phase as well as some RE-rich phase structure and the unchange of the axial preferred orientation is observed by the heat treatment.With the increasing of Al content,there are some RE(FeAl) 2 phase and RE(Al) phase precipitatied from the REFe2 matrix,and the morphology and distribution of the precipitated phase varys with the heat treatment,while the lamellar microstructure is degraded and the resistance of magnetic domain rotation for REFe2 phase is reduced.The magnetization and magnetostriction measurements show that heat treatment decreases the saturation magnetostriction of the Tb0.3 Dy0.7(Fe1-x Alx) 2 alloy(x = 0.05,0.15),and the saturation magnetostriction are 817 × 10-6,571 × 10-6,respectively.Compression strength and low-field dynamic response of the Tb0.3 Dy0.7(Fe1-x Alx) 2 alloy(x = 0.10) are significantly improved after heat treatment at 930 ℃ for 2 h and no reduction of saturation magnetostriction is detected.更多还原