The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 02, 1999
Filed:
Apr. 06, 1998
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
Provided by the invention is a method for the preparation of a magnetically anisotropic permanent magnet mainly consisting of crystallites of the Nd.sub.2 Fe.sub.14 B phase. The method comprises the steps of:(a) preparing an amorphous alloy of neodymium, iron and boron in molar fractions corresponding to the Nd.sub.2 Fe.sub.14 B phase or a nanocomposite of the Nd.sub.2 Fe.sub.14 B/Fe.sub.3 B or Nd.sub.2 Fe.sub.14 B/Fe system, for example, by the melt-spun method; and (b) subjecting the amorphous alloy of neodymium, iron and boron to a heat treatment in a magnetic field of at least 3 T (tesla) at a temperature in the range from 550 to 800.degree. C. for a length of time in the range from 1.times.10.sup.2 to 1.times.10.sup.4 seconds in an atmosphere of a non-reactive gas or vacuum.