Method of manufacturing ceramic magnets containing strontium or barium ferrite
Abstract
Abstract A METHOD OF MANUFACTURING A CERAMIC MAGNET CONTAINING STONTIUM FERRITE INCLUDES THE STEP FIRST PRODUCING A PARTICULATE MIXTURE OF CELESTITE AND FERRIC OXIDE IN SUCH PROPORTIONS THAT THE COMPOSITION OF THE STRONTIUM FERRITE IN THE RESULTANT MAGNET LIES IN THE RANGE SRO5.1FEO2O2 TO SRO6.0FEO3. THE PARTICULATE MIXTURE IN THEN HEATED IN THE PRESENCE OF A REACTION PROMOTING COMPOUND AT A TEMPERATURE SUFFICIENT TO CAUSE THE CELESTITE AND THE FERRUIC OXIDE TO REACT TOGETHER TO DIRECTLY FORM A PRODUC CONTAINING STRONTIUM FERRITE, THE REACTION PROMOTING COMPOUND BEING CHOSEN SO THAT ITS CATION FORMS A SULPHATE WHICH CAN BE REMOVED FROM THE PRODUCT BY LEACHING, SUBSEQUENTLY THE SULPHATE IS REMOVED FROM THE PRODUCT BY LEACHING. A MAGNET CONTAINING BARIUM FERRITE CAN ALSO BE MANUFACTURED BY THE PRESENT METHOD IN WHICH CASE A PARTICUKATE MIXTURE OF BARIUM SULPHATE AND FERRIC AXIDE IS PRODUCED AND HEATED IN THE PRESENCE OF THE PARTICULATE REACTION PROMOTING COMPOUND.
Inventors
- 👤 T Tombs
Bibliographic Details
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