METHOD FOR PRODUCING A MAGNETOCALORIC COMPOSITE MATERIAL AND COMPOSITE MATERIAL COMPRISING A MAGNETOCALORIC POWDER

摘要

The invention relates to a method for producing a magnetocaloric composite material, wherein a magnetocaloric powder, consisting of pulverulent particles (1) of a magnetocalorically active material, is mixed with a binder (3) in order to form a shaped body (9) using the composite material thus produced. In said method, a metal, or preferably a metal alloy with a low melting point of preferably less than 100°c, is used as the binder (3) and is heated to a temperature slightly above the melting point, in an activation step, a surface (4) of the particles (1) of the magnetocaloric powder is treated with an activating agent (5) and the wetting capability of the particles (1) is increased, in a subsequent embedding step, the surface-active magnetocaloric powder is introduced into the binder, such that the binder envelops the particles (1) and forms a bond with the surface of the particles (1), and in a subsequent separation step, the enveloped particles (1) of the magnetocaloric powder are separated from an excess portion of the binder that is not required for enveloping the particles (1). Hydrogenated lanthanum-iron-silicon-manganese La (Fe,Si,Mn) ₁₃H can be used as the magnetocaloric powder. An alloy consisting of bismuth, indium, zink and lead with a melting point of less than 85°C, preferably less than 80°C, can be used as the binder (3). Soldering fluid is preferably used as the activating agent (5).