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:
Jun. 24, 1997
Filed:
Oct. 27, 1995
Dmitrii Victorovich Golberg, Tsukuba, JP;
Kazuhiro Otsuka, Tsukuba, JP;
Tatsuhiko Ueki, Tokyo, JP;
Hiroshi Horikawa, Tokyo, JP;
Kengo Mitose, Tokyo, JP;
Abstract
A method of manufacturing a high-temperature shape memory alloy includes the steps of cold-working a high-temperature shape memory alloy, in which a reverse martensite transformation start temperature (As) in a first heating after cold working reaches 350.degree. C. or above. Thereafter, the cold-worked alloy undergoes a first heat treatment for a period of time within the incubation time required for recrystallization or less, and at a temperature higher than a reverse martensite transformation finish temperature (Af). Finally, the resultant alloy is annealed with a second heat treatment, at a temperature which is not less than the plastic strain recovery temperature and not more than the recrystallization temperature. Specifically, the first heat treatment is performed for a period of three minutes or less at a temperature which exceeds 500.degree. C. and which is lower than the melting point of the alloy. The composition of the high-temperature shape memory alloy is Ti.sub.50 Ni.sub.50-x Pd.sub.x (x being 35 to 50 at %), Ti.sub.50-x Ni.sub.50 Zr.sub.x (x being 22 to 30 at %), Ti.sub.50-x Ni.sub.50 Hf.sub.x (x being 20 to 30 at %) or the like.