We have fabricated spherical La (Fex Si1-x) 13 compounds by a rotating electrode process (REP) to provide suitable refrigerants for active magnetic regenerator (AMR)-type systems. In the as-prepared state, the cross section exhibits a dendritic metallographic structure composed of two phases of α-Fe -based alloy with Si and LaFeSi equiatomic compound. After annealing at 1323 K for 5 days, the spheres become a single phase of La (Fex Si1-x) 13. From the temperature dependence of magnetic entropy change for the hydrogenated spheres, it has been confirmed that the hydrogen concentration in the spheres is homogeneous. In addition, it has also been demonstrated that the itinerant-electron metamagnetic transition appears in the spheres with the higher Fe concentration. Consequently, the spherical La (Fex Si1-x) 13 fabricated by the REP are suitable for AMR-type refrigerations.
ASJC Scopus subject areas
- Physics and Astronomy(all)