OXIDE MAGNETIC MATERIAL, FERRITE PARTICLE, SINTERED MAGNET, BONDED MAGNET, MAGNETIC RECORDING MEDIUM AND MOTOR

摘要

There are provided a ferrite magnet having a high residual magnetic flux density and a high coersive force, that have not been accomplished by conventional hexagonal system ferrite magnets, by realizing a hexagonal system ferrite having a high saturation magnetization and a high magnetic anisotropy, a ferrite magnet having extremely excellent characteristics of the coersive force, and a coersive force which does not much drop particularly in a low temperature range, a ferrite magnet produced using relatively coarse ferrite particles having a grain size of above 1 mu m and having a high residual magnetic flux density and a high coersive force, and a magnetic recording medium having a high residual magnetic flux density and being thermally stable. Ferrite particles, a sintered magnet, a bonded magnet, a magnetic recording medium, etc., are constituted by using an oxide magnetic material comprising an oxide magnetic material which contains a ferrite having a hexagonal system structure as the main phase and having a composition comprising 1 to 13 at% of A, 0.05 to 10 at% of R, 80 to 95 at% of Fe and 0.1 to 5 at% of M based on the total of the metal elements of A, R, Fe and M to where A is at least one kind of elements selected from the group of Sr, Ba, Ca and Pb and essentially including Sr, R is at least one kind of elements selected from rare earth elements (inclusive of Y) and Bi and essentially including La and M is Co alone, or both Co and Zn.