LaFeSi-base magnetic refrigeration composite block body material based on grain boundary diffusion technique and preparation method of composite block body material

The invention discloses a LaFeSi-base magnetic refrigeration composite block body material based on a grain boundary diffusion technique and a preparation method of the composite block body material.The preparation method comprises the steps of uniformly mixing LaFeSi magnetic refrigeration material particles with La-Co alloy particles, processing the mixture into a block body through vacuum thermal mold pressing, carrying out diffusion annealing thermal treatment, so as to obtain the composite block body material, wherein the LaFeSi magnetic refrigeration material particles are LaFe12-xSix materials, and x is more than or equal to 1.0 and less than or equal to 1.6. The preparation method has the advantages that the composite material consists of a thermomagnetic working medium and a binder, and the porosity of the material is reduced by virtue of the binder, so that the high-density and high-thermomagnetic property LaFeSi-base magnetic refrigeration composite material is obtained, and the problems that a LaF