简介 |
PROBLEM TO BE SOLVED : To provide a method of manufacturing a sintered ferrite magnet which has a magnetoplumbite type crystal structure.
SOLUTION : The sintered ferrite magnet has a basic composition represented by the following general formula : (A1-xRx)O.n[(Fe1-yMy)2O3] by atomic ratio, wherein A is Sr, Sr or Ba, R is at least one of rare earth elements including Y and surely includes La, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn and surely includes Co, and x, y and n are numbers meeting the conditions of 0.01≤x≤0.4, [x/(2.6n)]≤y≤[x/(1.6n)], and 5≤n≤6. The ferrite magnet is obtained by : uniformly mixing a compound of the A element with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element, the M element, and Fe3O4 of 0.1-11 wt.% of the total content of Fe based on a Fe element to the resultant calcined powder at a pulverization step thereof; making powder of 0.7-0.9 μm of a mean particle diameter; molding slurry of the powder in a magnetic field; and sintering the resultant molded product.
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