Enhanced mechanical properties and large magnetocaloric effects in bonded La(Fe, Si)_(13)-based magnetic refrigeration materials

摘要

Bonded La(Fe, Si)_(13) magnetic refrigeration materials have been prepared, and the microstructure, mechanical properties, and magnetocaloric effect (MCE) of bonded LaFe_(11.7)Si_(1.3)1.3C_(0.2)H_x have been investigated systematically. Bonded materials show porous architecture, and the mechanical properties increase with the increase of epoxy resin content, which could fill more pores and boundaries and thus enhance the binding force between different particles. Bonded LaFe_(11.7)Si_(1.3)C_(0.2)H_(1.8) with 3wt. % epoxy resin exhibits a compressive strength of 162 MPa, 35% higher than that of bulk compound. The mass magnetic entropy change (ΔS_M) remains nearly unchanged while the volumetric ΔS_M reduces due to the decrease of density in bonded materials. For a low magnetic field change of 2T, the maximum ΔS_M value of bonded LaFe_(11.7)Si_(1.3)C_(0.2)H_(1.8) is ～10.2 J/kg K and ～54.7 mJ/cm~3 K, which is larger than those of some magnetocaloric materials in the same temperature range. Enhanced mechanical properties and great MCE suggest that bonded La(Fe, Si)_(13)-based materials could be promising candidates of magnetocaloric materials for practical applications of magnetic refrigeration.