PURPOSE: To manufacture a rare earth bonded magnet, which is improved in productivity and the stability of quality, has a high density and is superior in magnetic characteristics, by a method wherein a non-metallic inorganic binder is used in a method of manufacturing the magnet.
CONSTITUTION: An alloy of 10 to 30 atomic % of R (a Y-containing rare earth element), 2 to 28 atomic % of boron and 65 to 82 atomic % of M (iron, cobalt or nickel) is fused and a nonmetallic inorganic binder is added to a magnet power body manufactured by a quenching thin strip method using the fused alloy to mold the magnet powder body. The molded material is heat-treated at 600-900°C in a inert atmosphere and a powder body bond due to fusing of the binder is performed. The binder is a phosphorus oxide, a vanadium oxide, a low-temperature glass or the like, which is fused at a low temperature and is fused out on the surface of the molded material to have an action to fill pores in the surface. After the heat treatment is performed, a high-density treatment using a high isostatic press of an atmospheric pressure of 100 to 6000 is further performed at 600 to 900°C in an inert atmosphere.
OKUDA MASANAO
IKEDA KIWA
