(1. 蘭州理工大學(xué) 甘肅省有色金屬新材料重點(diǎn)實(shí)驗(yàn)室，蘭州 730050；
2. 蘭州理工大學(xué) 溫州泵閥工程研究院，溫州 325105)
摘 要: 采用區(qū)熔定向凝固方法制備<110>取向的Tb0.3Dy0.7(Fe1−xAlx)2(x=0,0.05,0.10,0.15)超磁致伸縮合金，研究不同含量Al原子替代Fe原子對于合金微觀組織、磁致伸縮性能和力學(xué)性能的影響。結(jié)果表明：Al原子替代不改變定向凝固樣品形成的<110>軸向擇優(yōu)取向，合金依然保持MgCu2型立方Laves相和部分稀土相結(jié)構(gòu)。隨著Al含量的增加，黑色RE(FeAl)2相和白色富稀土RE(Al)相的析出數(shù)量、尺寸及分布發(fā)生變化。微量Al原子(x≤0.05)替代可以顯著提高材料低磁場下的動(dòng)態(tài)響應(yīng)及飽和磁致伸縮系數(shù)，隨著Al含量進(jìn)一步提高，合金系飽和磁致伸縮系數(shù)降低。Tb0.3Dy0.7(Fe1−xAlx)2(x=0,0.05,0.10,0.15)合金的壓縮強(qiáng)度隨著Al原子含量增加而增加，合金發(fā)生解理斷 裂。當(dāng)Al替代量x≤0.1時(shí)，合金具有良好的綜合性能。
關(guān)鍵字: Tb-Dy-Fe合金；顯微組織；磁致伸縮；力學(xué)性能
（1. State Key Laboratory of Gansu Advanced Nonferrous Materials,
Lanzhou University of Technology, Lanzhou 730050, China;
2. Wenzhou Pump & Value Engineering Research Institute, Lanzhou University of Technology, Wenzhou 325105, China）
Abstract:The <110> oriented Tb0.3Dy0.7(Fe1−xAlx)2(x=0, 0.05, 0.10, 0.15) alloy was prepared by the method of zone-melting directional solidification. The effects of substituting Al for Fe on the microstructure, magnetostriction and mechanical properties were systemically investigated. The results show that the primary phase of Tb0.3Dy0.7(Fe1−xAlx)2 alloy were MgCu2-type cubic Laves phase structure and some RE phase, and the Al substitution doesn’t change the axial preferred orientation. With the increase of Al content, there are some RE(FeAl)2 phase and RE(Al) phase precipitated from the REFe2 matrix, and the quantity, size and distribution of the second phase vary with Al content increasing. The magnetization and magnetostriction measurements show that a small amount of Al substitution (x≤0.05) is beneficial to a decrease in the magneto crystalline anisotropy, and the saturation magnetostriction and dynamic response in low magnetic field increase drastically. With the increase of Al content, the saturation magnetostriction decreases distinctly, while the compressive strength increases. The fracture of the Tb0.3Dy0.7(Fe1−xAlx)2 alloy is cleavage fracture. The alloy with Al substitution range from 0 to 0.1 has optimal performances.
Key words: Tb-Dy-Fe alloy; microstructure; magnetostriction; mechanical property
