A Low Temperature Route for the Synthesis of Rare Earth Transition Metal Borides and Their Hydrides
作者:S. Kramp、M. Febri、J.C. Joubert
DOI:10.1006/jssc.1997.7333
日期:1997.10
Synthesis of rare earth-based alloys by the ORD technique consists in the reduction of rare earth oxides in a melt of calcium under argon, and simultaneous diffusion–reaction of the just formed rare earth metal with the other elements. This method has been applied with success to numerous ternary borides containing transition metals such as the magnetic alloys Y2Co14B, LnCo4B, and YCo3B2. By using
通过ORD技术合成稀土基合金包括在氩气下还原钙熔体中的稀土氧化物,以及刚形成的稀土金属与其他元素的同时扩散反应。该方法已成功应用于许多含过渡金属的三元硼化物,例如磁性合金Y 2 Co 14 B,LnCo 4 B和YCo 3 B 2。通过使用少量过量的Ca,硼化物颗粒会在含有未反应(熔化)的Ca和纳米级CaO颗粒的粘性浆料介质中生长。单相硼化物合金可以在1000°C下获得,具有很高的晶体质量的松散的微米级颗粒,这由相应的X射线图上的尖锐衍射峰所证实。通过在稀释的弱酸溶液中轻轻洗涤,然后在室温下真空干燥,可以轻松回收颗粒。这种相当低的温度技术特别适合于不一致的熔化相的合成,以及含有挥发性稀土元素(Sm,Yb,Tb等)的合金。