| 摘要 |
PURPOSE:To manufacture a high density massive permanent magnetic alloy having high energy product value by subjecting the molten metal of an Fe-Nd-B alloy having specific compsn. to ultrarapid cooling into the amorphous shape, finely pulverizing it and subjecting the pulverized material to hot extrusion CONSTITUTION:The molten metal of an alloy of which 0.3 to 3wt.% HfF2 is mixed into the essential components having the compsn. of FeaCobNdcRdMeBf (in the formula, R denotes one kind among La, Y, Ce, Dy, Tb, Pr or the mixture thereamong, M denotes one kind among Al, Si, Ge, Ga or the mixture thereamong and (a)+(b)+(c)+(d)+(e)+(f)=100 and, by atom, 65 to 84%(a), 0 to 25%(b), 5 to 20% (c), 0 to 5% (e) and 3 to 10% (f) are regulated) is rapidly cooled at 10<5> to 10<7> deg.C/sec cooling speed in a nonoxidizing atmosphere into the thin layer of an amorphous phase, etc., which is finely pulverized and is subjected to hot extrusion. The HfF2-contg. Fe-Nd-B base permanent magnetic alloy in which <=0.5mum HfF2 grains are uniformly dispersed, provided with hard magnetism and having high energy product value can be manufactured. |
