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:
Mar. 20, 1990
Filed:
Feb. 26, 1986
Mohamed Nazmy, Fislisbach, CH;
Hans Rydstad, Birmenstorf, CH;
BBC Brown, Boveri & Company, Limited, Baden, CH;
Abstract
A process for increasing the oxidation resistance and corrosion resistance of a component made of a dispersion strengthened superalloy by means of a surface treatment, the object of which in every case is to produce or retain a fine-grained surface zone (5) while the core zone (4) of the component in all circumstances is forced to form coarse grains during the final recrystallization annealing in the temperature range between the recrystallization temperature and the solidus temperature. A fine-grained surface zone (5) is produced by cold-working the surface zone (3, 5) by shot-peening, surface milling or pressing or by heating the surface zone (7) to a temperature about 100.degree. to 140.degree. C. below the recrystallization temperature by means of a laser (9) or an arc (10) while the core zone is kept at less than 900.degree. C., or by application of a 10 to 50 .mu.m thick nickel layer onto the surface followed by diffusion of the nickel into the surface zone (nickel-rich surface layer 14) of the component at a temperature below the recrystallization temperature. In each case, recrystallization annealing in order to establish coarse grains in the core zone (4) is finally carried out.