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. 27, 2001
Filed:
Jun. 07, 2000
Koichi Hirota, Fukui-ken, JP;
Takahiro Hashimoto, Fukui-ken, JP;
Koji Sato, Fukui-ken, JP;
Kenji Yamamoto, Fukui-ken, JP;
Takehisa Minowa, Fukui-ken, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
Disclosed is a thin alloy ribbon prepared by the strip casting method as an intermediate for the preparation of a sintered rare earth-based permanent magnet or in particular, a neodymium/iron/boron-type permanent magnet. The thin alloy ribbon is characterized by a specific volume fraction of the four-phase coexisting region consisting of the &agr;-iron phase, R-rich phase, R,T,B,phase and R,T,B phase each having an average grain diameter in a specified range and a specific volume fraction of the chill crystalline phase. When these requirements are satisfied, the sintered rare earth-based permanent magnet prepared from the thin alloy ribbons can be imparted with improved magnetic properties and high sintering density even without increasing the sintering temperature.