| 摘要 |
PURPOSE:To prevent a resin-bound magnet from deteriorating due to oxidation and to avoid a decrease in the magnetic property of the magnet by containing as main ingredients specific rare-earth metal and transition metal, surface treating with zinc phosphate magnetic powder, then treating it with inorganic chromic acid, compression molding it, then curing and solidifying a binder, and impregnating its air gap with synthetic resin. CONSTITUTION:A porous molding formed by surface treating with zinc phosphate magnetic powder, then treating it with inorganic chromic acid, compression molding it and then curing and solidifying a binder is impregnated at its air gap with synthetic resin. Intermetallic compound magnetic powder which contains as main ingredients rare-earth metal and transition metal is magnetic powder of R-Fe-B (where R is Nd and/or Pr, or part of them is substituted for one or more rare earth element) SmCo5, Sm2Co17 alloy magnet, and its particle size is preferably approx. 1-150mum. The zinc phosphate preferably uses zinc phosphate film treating agent, and BrO3 is exemplified as its assistant. Chromic acid anhydride or the like is used as the inorganic chromic acid, and synthetic resin as the binder preferably contains 50-95pts.vol. of the powder and 50-5pts.vol. of synthetic resin at the mixing ratio of the powder and the resin. |
