采用高能球磨法制备了Mn1.0Fe0.9-xCrxP0.5Si0.5(x=0,0.02,0.04,0.06,0.08,0.10(原子分数))和Mn1.0-xCrxFe0.9P0.5Si0.5(x=0,0.02,0.04,0.06,0.08(原子分数))两个系列化合物。利用X射线衍射和磁性测量技术研究了材料的晶体结构,磁性和磁热效应,研究结果表明:两个系列化合物均结晶为Fe2P型六角结构,空间群为P62 m。通过调整Cr元素的掺杂量,可将该磁热材料的居里温度调节在155~375K范围。随Cr含量增加,化合物的最大磁熵变逐渐变小,但等温磁熵变随温度变化曲线的半峰宽变宽,相对制冷能力变大。
Mn1.0F0.9-xCrx P0.5 Si0.5 (x = 0,0. 02,0.04,0.06,0. 08,0. 10(atom fraction)) and Mn1.0-x Crx Fe0.9 P0. 5 Si0.5(x= 0,0.02,0. 04,0. 06,0. 08 (atom fraction)) were synthesized using mechanical alloying and high temperature sintering method. The crystal structure, magnetic and magnetocaloric properties were studied by using X-ray diffractometer and magnetic magnetometer. Both of the two series compounds crystallize in Fe2 P-type hexagonal structure with space group of P62m. The Curie temperature can be tuned within a range of 155-375 K by varying the Cr concentration. The maximum magnetic entropy change decreases with increasing Cr content. The full width at half maximum (FWHM) of the magnetic entropy change curves and the relative cooling power (RCP)increase with increasing Cr content.