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:
May. 23, 1995
Filed:
Jun. 03, 1993
Applicant:
Inventor:
Jean-Marc Rongvaux, La Norville, FR;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C21D / ;
U.S. Cl.
CPC ...
148675 ; 148555 ;
Abstract
A nickel-based superalloy known by the designation '718' and having a typical composition comprising, in percentages by weight, Cr 19, Fe 18, Nb 5, and the remainder Ni, is subjected, after the usual thermo-mechanical and heat treatment steps, to an additional annealing step wherein the temperature and duration are selected from the following range as desired: 800.degree. C. for between 5 and 30 hours; 750.degree. C. for between 25 and 70 hours; and 700.degree. C. for between 100 and 300 hours. This leads to a definite improvement in the behaviour of parts made from the superalloy, in terms of fatigue cracking, when used at temperatures over 650.degree. C.