SURFACE RUST PREVENTION AND PERFORMANCE IMPROVING TREATMENT OF MAGNETIC MATERIAL

摘要

PROBLEM TO BE SOLVED: To prevent deterioration in the magnetic properties of an alloy type and an intermetallic compound type magnetic material resultant from oxidation from an oxygen source present in the atmosphere. SOLUTION: Because material metal for a rust preventive coating to be formed on the surface of an alloy type and an intermetallic compound type magnetic material is supplied in a highly activated state by being heated in a hermetically sealed vessel, a sorption takes place uniformly in three dimensions with respect to the surface of the magnetic material of solid form and the metal is deposited all over the surface. By this procedure, a superior rust preventive metal coating can be formed and deterioration in magnetic properties due to oxidation in the air can be suppressed. Moreover, the supplied metal effectively forms, by the interdiffusion and reaction between a constituent present in the vicinity of the surface of the magnetic material and itself, a new alloy phase or intermetallic compound phase and can contribute to further improvement in the magnetic properties and the rust preventive effect.