| 摘要 |
PURPOSE:To obtain the Nd-Fe-B magnet which is optimum for a bonded magnet having the residual magnetic flux density of 5kG or higher by a method wherein Fe-Ni-B-(Nd, Pr and Dy)-M alloy melted metal of specific structure, having a small content of rare earth element, is superquenched, heat-treated and a microscopic crystal aggregate is formed. CONSTITUTION:The title magnet alloy is the composition of Fe100-x-y-zNixBy(R1-aDya)zMw (one or two kinds of Pr and Nd, M indicates one or two or more kinds of Al, Si, Cu, Ga, Ag and Au) which satisfies the following limit simbols: 0.01<=x<=2atomic%, 16<=y<=22atomic%, 3<=z<=5.5atomic%, 0.02<=a<=0.9atomic% and 0.1<=w<=3atomic%. The above-mentioned molten alloy is super-quenched and an amorphous structure is obtained. A microscopic crystal aggregate is formed by heat-treating the obtained ribbon. Besides, an Fe3B type compound phase which is the main phase, the quantum ratio of the ferromagnetic phase, having Nd2Fe14B type crystal structure, is increased. By forming the above- mentioned material into magnet alloy powder, the magnet alloy powder optimum for the bonded magnet can be obtained. |
