GRADED POWDER COATINGS FOR MAGNETIC APPLICATIONS AND PROCESSFOR PRODUCING THE SAME

摘要

A method for producing composite insulating coatings on powder particles, the coatings containing an electrically insulating metal compound and an organic polymer. The coatings are deposited preferably by controlled spraying, simultaneous or sequential, of sol precursors of insulating metal compounds and polymer emulsions or solutions onto polymer, metal or ceramic powder particles preferably during the blending or mixing of the particles. The process is useful for mass production of coated iron-based powders used for shaping components by powder metallurgy techniques for magnetic applications. Coated iron based powders can be cold or warm pressed and heat treated to obtain the desired mechanical properties.