| 摘要 |
PURPOSE:To prepare a permanent magnet having a specified crystal structure and magnet characteristics, by heating an alloy containing iron, platinum, Ti and impurities in each specified ratio, under specified conditions, and subjecting it to a homogeneous solution heat treatment quick cooling, and thereafter, reheating and cooling again. CONSTITUTION:An alloy containing 54-67% iron, 33-45% platinum, 0.1-5% Ti and <=0.5% impurities in terms of atomic ratio is heated for 1min-50hr at 900-1,400 deg.C, is homogenized and subjected to solution heat treatment and thereafter, is quickly cooled at a speed of >=30 deg.C/min-<=2,000 deg.C/sec in the water or in the air. Subsequently, it is reheated for 1min-300hr at 450-750 deg.C, and thereafter, is cooled. An alloy obtained in this way has gamma1 single phase of a face- centered tetragonal type, and a 2 phase coexistent state that the gamma1 phase is equally dispersed and precipitated in mother phase of gamma phase of a face-centered cubic type, the coercive force is >=500 oersted, the residual magnetic flux density is >=5 kilo gauss, and the maximum energy product is >=2 mega gauss oersted. |
