MAGNETOPLUMBITE-TYPE HEXAGONAL CRYSTAL FERRITE MAGNETIC POWDER AND METHOD FOR PRODUCING SAME

There are provided a magnetoplumbite-type hexagonal crystal ferrite magnetic powder which can be suitably used as the material of a radio wave absorber having an excellent radio wave absorbing power in the 76 GHz band, and a method for producing the same. In a method for producing a magnetoplumbite-type hexagonal crystal ferrite magnetic powder, the method comprising the steps of: mixing powders of the raw materials of a magnetoplumbite-type hexagonal crystal ferrite magnetic powder, which is expressed by a compositional formula of AFe(12-x)AlxO19 (A is at least one selected from the group consisting of Sr, Ba, Ca and Pb, x=1.0 to 2.2), to obtain a mixture; granulating and molding the mixture to obtain molded bodies; firing the molded bodies to obtain fired bodies; and pulverizing the fired bodies, there are prepared a plurality of firing containers (firing scabbards 10), each of which has an opening of the upper face thereof and a notch (10a) formed in the upper portion of the side face thereof so as to be communicated with the outside thereof, each of the firing containers being filled with the molded bodies, and the firing containers being stacked in a plurality of stages so as to close the opening of the top face of the lower firing container, to fire the molded bodies in a firing furnace (20).