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.

Date of Patent:
Apr. 11, 1978

Filed:

Apr. 21, 1976
Applicant:
Inventors:

Masaru Kobayashi, Tokyo, JA;

Atsuya Kamada, Kamakura, JA;

Takao Terabayashi, Yokohama, JA;

Hiroshi Asao, Yokohama, JA;

Assignee:

Hitachi, Ltd., Tokyo, JA;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B21D / ;
U.S. Cl.
CPC ...
72364 ; 72700 ; 148 / ; 148125 ;
Abstract

Improvements in a plastic working process for face-centered cubic metals, and titanium and zirconium having close-packed-hexagonal lattice, which process utilizes a phenomenon that the ductility of these metals is increased at sub-zero temperatures, i.e., temperatures below 0.degree. C. This process includes the steps of (i) imparting plastic flow including at least a uniaxial tensile stress field a metal at a temperature below zero, (ii) subjecting the metal to plastic flow to an extent that the strain of the metal is within the limit of uniform elongation of the metal, and then to plastic flow including at least a uniaxial tensile stress field continuously thereafter, or (iii) using frost as a lubricant for plastic working at temperatures below 0.degree. C according to either one of the foregoing steps.


Find Patent Forward Citations

Loading…