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. 09, 2000
Filed:
May. 23, 1997
Mark Gilbert Benz, Burnt Hills, NY (US);
Michael Francis Henry, Niskayuna, NY (US);
Charles Philip Blankenship, Jr, Niskayuna, NY (US);
Aldo Enrique Murut, Schenectady, NY (US);
General Electric Company, Schenectady, NY (US);
Abstract
A method combining isothermal and high retained strain forging is described for Ni-base superalloys, particularly those which comprise a mixture of .gamma. and .gamma.' phases, and most particularly those which contain at least about 40 percent by volume of .gamma.'. The method permits the manufacture of forged articles having a fine grain size in the range of 20 .mu.m or less. The method comprises the selection of a fine-grained forging preform formed from a Ni-base superalloy, isothermal forging to develop the shape of the forged article, subsolvus forging to impart a sufficient level of retained strain to the forged article to promote subsequent recrystallization and avoid critical grain growth, and annealing to recrystallize the microstructure. The method permits the forging of relatively complex shapes and avoids the problem of critical grain growth. The method may also be used to produce location specific grain sizes and phase distributions within the forged article.