Rare-earth elements in permanent magnets and superconducting compounds and alloys (except new high T c ceramics) as thin films, thin crystals and thinned bulk materials
Over about 20 years the synthesis of new alloys and compounds has developed greatly. In the field of superconductor and permanent magnet materials one can claim a ‘true revolution’. The particular magnetic and electronic properties of the rare earth elements make them very attractive for the fabrication of new permanent magnets, which contain at least one rare earth element, is possibly only a step towards the elaboration of new alloys and/or compounds. This review paper recalls the results and properties relative to super magnets (since 1981) and superconductors (except the new T c) (since 1960) as thin and thick films, thin crystals and thinned bulk materials up to 1988. This review shows how numerous research teams have followed different and various routes to increasingly improved specimens. Crystallographic and chemical interpretations and conclusions will be compared and discussed. Some applications will be described.
