低磁场条件下（Gd1-xREx）5Si4（RE：Dy,Tb；x=0、0.1、0.125、0.15）合金磁热效应研究术

Low-field magnetocaloric effect in （Gd1-xREx）5Si4（RE：Dy,Tb;x=0、0.1、0.125、0.15） alloys

用高频真空悬浮炉在氲气保护下制备了（Gd1-xREx）5Si4（RE：Dy,Tb；x=0、0.1、0.125、0.15）和（Gd1-xREx）5Si4（x=0.1、0.125）合金样品，用直接测量方法测定了在永磁体提供的低磁场（H=1．3T）条件下样品的磁热效应曲线（△Tab-T）；结果表明，用稀土金属Dy、Tb分别部分替代Gd5Si4合金中的Gd原子，不能增强合金的磁热效应，但可在333～300K范围改变材料的居里温度，且磁热效应峰值范围变宽．

A series of （Gd1-xREx）5Si4（RE：Dy,Tb;x=0、0.1、0.125、0.15） alloys have been prepared by high frequency induction melting method in argon atmosphere. The magnetocaloric effect （△Tab-T） curves of the alloy samples have been determined directly in the low field （H=1.3T） produced by permanent magnet, the results indicate that the substitutions of Dy or Tb for Gd of Gd5Si4 alloy do not enhance the MCE, but change the Curie temperature from 333 to 300K. and the MCE peak becomes broadened.