Abstract: A magnetocaloric effect heterostructure having a core layer of a giant magnetocaloric material and an elastically stiff material layer coated on at least one surface of the magnetocaloric material layer. The elastically stiff material layer restricts volume changes of the core layer during application of a magnetic field to the heterostructure. A magnetocaloric effect composite powder including a plurality of core particles of a giant magnetocaloric material. Each of the core particles is encapsulated within a coating of elastically stiff material that restricts volume changes of the core particles during application of a magnetic field thereto. A method for enhancing the magnetocaloric effect within a giant magnetocaloric material including the step of coating a surface of the magnetocaloric material with an elastically stiff material. The elastically stiff material restricts volume changes of the magnetocaloric material during application of a magnetic field thereto.

Abstract: A mixture including at least one iron oxide and a mon-magnetic matrix material is melted or vaporized and then heat is rapidly removed from the material. The resulting magnetic oxide precipitates are densely packed in the non-magnetic matrix. The precipitates have a narrow particle size distribution which results in a high signal-to-noise ratio when the oxides are used for magnetic recording purposes. The non-magnetic matrix can be removed to yield homogeneous, small particle iron oxide containing magnetic powder. Alternatively, the non-magnetic matrix/iron oxide material can be processed to yield a shaped recording medium.