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. 12, 1991
Filed:
Jun. 18, 1990
Katsuhiko Murakami, Tokyo, JP;
Nobuo Yamagami, Tokyo, JP;
Toshiyuki Nakanishi, Yokosuka, JP;
Iwao Nakano, Yokosuka, JP;
Keiichi Kobayashi, Tokyo, JP;
Takashi Yoshikawa, Tokyo, JP;
NKK Corporation, Tokyo, JP;
Japan Marine Science and Technology Center, Yokosuka, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
A method for manufacturing an alloy rod having giant magnetostriction, which comprises the steps of: supplying a rod-shaped alloy material, comprising at least two rare earth metals including terbium and dysprosium and at least one transition metal, into a crucible moving downwardly at a speed of from 0.2 to 8.5 mm/minute in an inert gas atmosphere kept under a pressure of from 0.2 to 10 atm.; heating the rod-shaped alloy material in the circumferential direction thereof in the crucible by means of an annular high-frequency heating coil having a frequency of from 0.1 to 3 MHz and having an inside diameter of from 1.1 to 1.6 times as large as an outside diameter of the crucible, arranged so as to surround the crucible; continuously moving the heating from the lower end toward the upper end of the alloy material to locally and sequentially melt the alloy material in the axial direction thereof; and then locally and sequentially solidifying the resultant molten section of the alloy material in the crucible, thereby manufacturing an alloy rod having giant magnetostriction comprising a single-crystal structure or a unidirectional-solidification structure consistent with the axial line thereof.