La_(1-x)Pr_xFe_(11.4)Si_(1.6)(x=0.1,0.2,0.3)金属间化合物的晶体结构和磁熵变研究

Study on the crystal structure and magnetic entropy change properties of La_(1-x)Pr_xFe_(11.4)Si_(1.6)(x=0.1,0.2,0.3) inter metallic compounds

通过X射线和磁性测量等手段对所制备的金属间化合物La1-xPrxFe11.4Si1.6(x=0.1,0.2,0.3)的结构和磁性进行了研究.结果表明,在1 373 K温度下,经过50 d退火所得的化合物均形成了单相立方NaZn13型结构;部分Pr替代La原子后,会引起晶格畸变;另在外磁为1.5 T时,Pr含量为x=0.1,0.2,0.3时的最大磁熵变|ΔS(T,H)M|max分别为15.06,37.08和15.22 J/kg.K.大的磁熵变来源于TC处磁化强度的陡峭变化和TC以上磁场诱发的巡游电子变磁转变.

The crystal structure and magnetic properties of La1-xPrxFe11.4Si1.6(x=0.1,0.2,0.3) were investigated by means of X-ray powder diffraction and magnetic measurements.X-ray diffraction patterns reveal that the compounds annealed at 1373 K for five days remain the single phase of cubic NaZn13-type structure.The substitution of Pr for La leads to the reduction of the unit-cell volume.The maximum values of isothermal entropy change |ΔS(T,H)M|max in compounds La1-xPrxFe11.4Si1.6 is 15.06 J/kg·K and 15.22 J/kg· K,...