Gd-Tb-Nd系室温磁致冷材料研究

对适用于室温区磁致冷的Gd Tb Nd系合金进行了研究。样品用Ar气保护的高频磁浮炉熔炼 ,用振动样品磁强计测量了不同温度下的磁化曲线。根据整理的磁热曲线计算出材料的磁熵改变值。结果表明 :GdxTbyNd( 10 0 -x - y) 系磁致冷材料的居里温度在室温附近 ,Tb和Nd含量的增加使居里温度降低 ;Nd含量较小时Gd Tb Nd系具有较大的磁熵改变值 ;少量Nd的加入可显著改变居里温度 ,是十分有效的制冷温区调节剂。因此 ,采用不同成分的Gd Tb Nd系材料的组合 ,可望实现在低磁场下室温附近较大温度范围的磁制冷热循环。

Experimental Study of Room Temperature Magnetic Refrigerate Materials Gd-Tb-Nd System

A system of magnetic refrigerants suited for room temperature, Gd Tb Nd, is studied. Samples were melted by argon-protected high frequency magnetic induction furnace. Magnetization lines were measured by vibrating sample magnetometer, and were processed to obtain magnetic entropy change. Experimental results show Curie temperature of Gd Tb Nd system is near room temperature and decrease with the increasing of Tb and Nd content. With a small amount addition of Nd the magnetic entropy change is comparable with that of Gd Tb. A Small amount addition of Nd can influence T c greatly, so that it can be used as regulator of regulate refrigerate temperature range. Gd Tb Nd system materials is prospective selection to realize large scale room temperature refrigeration with low magnetic field.