Manufacturing method of permanent magnet material

Abstract

Abstract PURPOSE:To obtain an Nd-Fe-B permanent magnet material having excellent magnetic characteristics by packing the powder formed by pulverizing a thin strip obtd. by quick cooling and solidifying of an Nd-Fe-B alloy into a hermetic vessel, then making the packed material anisotropic by plastic deformation. CONSTITUTION:The thin strip prepd. by melting the Nd-Fe-B alloy expressed by the formula in an inert atmosphere, then cooling the melt by an ultra-quick cooling method is pulverized by; for example, a ball mill, etc. in accordance with the conventional practice. The fine powder obtd. in such a manner is packed into the hermetic vessel which is so constructed that an inert gaseous atmosphere or vacuum can be maintained. The powder may be preliminarily press-formed to a prescribed shape at a room temp. and may be formed in the state of the higher density in the case of packing the powder into the vessel. The powder or molding packed into the hermetic vessel is then subjected to the plastic deformation treatment by a method such as; for example, unidirectional pressing or rolling and is thereby made anisotropic. The plastic deformation is preferably so executed as to attain >=30% rate of deformation. The desired Nd-Fe-B permanent magnet material is obtd. by the above-mentioned method.

Inventors

• 👤 Takashi Furuya
• 👤 古谷　嵩司
• 👤 Norio Yoshikawa
• 👤 紀夫 吉川

Bibliographic Details