FERRITE MAGNETIC POWDER FOR BONDED MAGNETS, PROCESS FOR PRODUCTION THEREOF, AND BONDED MAGNETS

摘要

Ferrite magnetic powder for bonded magnets which is completely freed from hexavalent chromium acting as an environment load substance at a low cost without impairing the productivity or producing such an adverse effect on magnetic characteristics as to cause troubles in service; a process for the production of the magnetic powder; and bonded magnets. The formation of hexavalent chromium acting as an environment load substance is inhibited by a process which comprises the step of firing a raw material powder to obtain a fired powder, the step of wet-pulverizing the fired powder, the step of wet-washing the pulverized powder, and the step of annealing the resulting powder and in which the wet-pulverizing or the wet-washing is conducted while keeping the dispersing solvent at pH of 8.5 or below. ® KIPO & WIPO 2009