METHOD FOR MANUFACTURING A MAGNETOCALORIC ELEMENT, AND MAGNETOCALORIC ELEMENT THUS OBTAINED

摘要

A method for manufacturing a magnetocaloric element including the following steps:
a powder of a magnetocaloric alloy with composition:;La1-x(Ce,Pr)x((Fe1-z-vMnzCov)1-ySiy)wXn ;is prepared, wherein:
X is one or several elements selected from H, C, N and B;x=0 to 0.5;y=0.05 to 0.2;z=0 to 0.15;v=0 to 0.15;w=12 to 16;n=0 to 3.5;the remainder being impurities, with a maximum content of 4% by weight, preferably a maximum content of 2% by weight, of rare earths other than La, Ce and Pr, and a maximum content of 2% by weight, for the other impurities, the preparation of the powder including the following steps:a liquid alloy (4) is elaborated;it is solidified in the form of a powder of substantially spherical particles (14) with an average diameter comprised between 10 and 100 μm by atomization of a jet (8) by means of an inert gas;said powder (14) is heat-treated in order to give it at least 70% by weight of a structure of the NaZn13 type by heating up to a temperature from 900 to 1,200° C.;optionally, a hydridration and/or nitridation and/or carbidation and/or carbonitridation treatment is carried out for giving n its definitive value;said powder (14) is dispersed in a matrix formed by one or several organic binders for forming a mixture including from 40 to 80% by volume of powder;said mixture is shaped.

主权项

1. A method for manufacturing a magnetocaloric element comprising
La1-x(Ce,Pr)x((Fe1-z-vMnzCov)1-ySiy)wXn , wherein
X is one or several elements selected from the group consisting of H, C, N and B; x=0 to 0.5; y=0.05 to 0.2; z=0 to 0.15; v=0 to 0.15; w=12 to 16; n=0 to 3.5; the method comprising: elaborating a liquid alloy in a crucible; solidifying said liquid alloy in the form of a powder of substantially spherical particles with an average diameter comprised between 10 and 100 μm by atomization of a jet of said liquid alloy with an inert gas; optionally, heat-treating said powder at a temperature comprised between 100 and 500° C. for at least 1 min in a non-oxidizing atmosphere to remove compounds adsorbed by the powder; heat-treating of said powder to give it, at least at 70% by weight, a phase with a structure of the NaZn13 type by heating under an inert or reducing atmosphere or in vacuo up to a temperature from 900 to 1,200° C.; optionally, hybridizing and/or nitriding and/or carbidating and/or carbonitriding said powder to give n its definitive value; dispersing said powder in a matrix formed by one or several organic binders to form a mixture comprising 40 to 80% by volume of powder; shaping said mixture; and optionally solidifying the matrix, wherein said magnetocaloric element comprises a maximum content of 4% by weight of rare earths other than La, Ce and Pr, and a maximum content of 2% by weight, of other impurities.