Abstract: A magnetic refrigeration composition for magnetic refrigeration including at least three kinds of magnetic substances selected from the group consisting of magnetic substances having the formulaR'Al.sub.2, R'.sub.3 Al.sub.2, and R'Al.sub.2+.delta.wherein R' is at least one element selected from the group consisting of Gd, Tb, Dy, Ho and Er, provided that the total number of atoms satisfies the above formula and 0<.delta.<0.2, the composition being a mixture of the magnetic substances, wherein each kind of said at least three kinds of magnetic substances has a Curie temperature which is different from that of the other kinds and which preferably range up to about 77.degree. K.

Abstract: A magnetic refrigeration composition for magnetic refrigeration including at least three kinds of magnetic substances selected from the group consisting of magnetic substances having the formulaR'Al.sub.2, R'.sub.3 Al.sub.2, and R'Al.sub.2+.delta.wherein R' is at least one element selected from the group consisting of Gd, Tb, Dy, Ho and Er, provided that the total number of atoms satisfies the above formula and 0<.delta.<0.2, the composition being a mixture of the magnetic substances or a multilayered composition of the magnetic substances, and when a multilayered composition, each layer of the multilayered composition consists of one magnetic substance, wherein each kind of said at least three kinds of magnetic substances has a Curie temperature which is different from that of the other kinds and which preferably range up to about 77.degree. K.

Abstract: A magnetic refrigeration composition for magnetic refrigeration including at least three kinds of magnetic substances selected from the group consisting of magnetic substances having the formulaR'Al.sub.2, R'.sub.3 Al.sub.2, and R'Al.sub.2+.delta.wherein R' is at least one element selected from the group consisting of Gd, Tb, Dy, Ho and Er, provided that the total number of atoms satisfies the above formula and O<.delta.<0.2, the composition being a mixture of the magnetic substances or a multilayered composition of the magnetic substances, and when a multilayered composition, each layer of the multilayered comy position consists of one magnetic substance, wherein each kind of said at least three kinds of magnetic substances has a Curie temperature which is different from that of the other kinds and which preferably range up to about 77.degree. K.

Abstract: A magnetic refrigerator comprises a working material radiating heat when a magnetic field is applied thereto and absorbing heat when the magnetic field is removed therefrom, and magnetic coil which is movable for selectively applying or removing the magnetic field to or from the working material. Directional heat pipes are disposed between the working material and an object of cooling, whereby heat from the object of cooling is transmitted to the working material when the working material absorbs the heat, and whereby heat from the working material is prevented from being transmitted to the object of cooling when the working material radiates the heat.