Study on structure and magnetocaloric effect of mncogefenisi composites magnetic refrigeration material

Abstract

Mn16Fe16CoxNi34-xGe7Si27（x=1，3，6，7.5，9）series alloy were prepared by vacuum arc melting technology under the protection of argon flow and structure and magnetocaloric effects of MnCoGe-FeNiSi composite material was investigated . Using X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) method, structure and magnetocaloric effects of the alloys were analyzed, respectively. The results of the show that the alloys shift from low temperature type TiNiSi orthogonal structure into high temperature type Ni2In single-phase hexagonal structure with the increase of the content of Co alloy. Alloys exhibit reversible FM-PM first-order phase transformation, with thermal hysteresis decreased from 13 K to 9 K and the Curie temperature though room temperature, and magnetic entropy change can reach 15.6 J／(kg·K) for 0~1.5 T.