METHOD OF MANUFACTURING FULLY DENSE RARE EARTH-IRON BASED BOND MAGNET

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacturing a fully dense rare earth-iron based bond magnet which is provided with high dimensional accuracy and weather resistance together while maintaining a level of residual magnetization Mr or maximum energy product at a level of an original magnet flake.SOLUTION: The manufacturing method includes: a first step of kneading a thermosetting resin composition which is not viscous at the ordinary temperature but flowable with a yield strength with a rare earth-iron based magnet flake to manufacture a granular composite magnet material; a second step of filling a cavity with the composite magnet material and applying uniaxial pressure equal to or more than the yield strength of the thermosetting resin composition to the composite magnet material to reduce voids by interaction of plastic deformation of the thermosetting resin composition simultaneously with brittle fracture of the magnet flake, and laminating the composite magnet material in a pressure axis direction to manufacture a green compact in a specific shape in which a mutual positional relation between the magnet flakes is fixed substantially; and a third step of heating the green compact to harden the thermosetting resin composition constituting the green compact.