MnCo_(1-x)Ni_xGe化合物的磁热效应

Magnetocaloric Effect in MnCo_(1-x)Ni_xGe Compounds

在氩气保护下,用电弧熔炼法制备了MnCo1-xNixGe(x=0.05,0.1,0.15)系列化合物,用X线衍射和磁性测量研究了样品的晶体结构和磁熵变.结果表明:MnCo1-xNixGe系列化合物为TiNiSi型正交结构,空间群为Pnma,随着Ni含量的增加,居里温度由x=0.05时的330K降低到x=0.15时的322K;当x=0.05、外加磁场为1.5T时,化合物的最大磁熵变为1.86J/(kg.K);随着Ni含量的增加,该系列化合物的磁熵变略显降低趋势.

A series of MnCo1-xNixGe （x=0.05,0.10,0.15） compounds were prepared by arc melting under the high purity argon gas atmosphere and annealed at 1123K for 24h.The structure and magnetic entropy change of the MnCo1-xNixGe compounds were investigated by means of X-ray diffraction and magnetic measurements.The results show that all these compounds crystallize in TiNiSi type orthorhombic structure and space group is Pnma.The Curie temperature of the compounds decreases with increasing of the Ni content and can be varied from 330K to 322K.The maximal magnetic entropy change is 1.86J/（kg·K） for x= 0.05 under a 1.5T magnetic field change.Magnetic entropy change of the compounds slightly decreases with increasing of Ni content.