Raw material powder for manufacturing method

文件类型：PDF文档
文件大小：66K
PURPOSE : To produce a raw powder for an anisotropic bond magnet excellent in magnetic characteristic by successively heat-treating, hydrogenating and dehydrogenating a billet of specified composition under specified conditions. CONSTITUTION : A billet having 0.03-10mm thickness is cast by strip casting from the melt consisting of 9.0-15atomic % of rareearth element (contg. >=95% Pr, etc.), 5.5-8.0% B, 2-20% Co, etc., 0.01-2.0% Al, etc., and the balance Fe. The billet is heattreated in vacuum at 1000-1200 deg.C for 30min to 48hr to grow the crystal grain in the crystal region where the crystals are oriented in a fixed direction to >=20mum in the shortest direction. The billet is held at 750-900 deg.C for 15min to 8hr in gaseous H2 at 10-1000kPa and hydrogenated, and then the hydrogenated billet is held at 700-900 deg.C for 5min to 8hr at the H2 partial pressure of <=10kPa, cooled and crushed. A magnetically anisotropic alloy powder having 0.05-0.5mum average crystal grain diameter and 20-400mum average grain size is efficiently produced in this way.