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:
Dec. 01, 1992
Filed:
Dec. 09, 1991
Peter W Mueller, Morrow, OH (US);
Thomas F Berry, Cincinnati, OH (US);
Robert E Allen, Cincinnati, OH (US);
Christopher C Glynn, Hamilton, OH (US);
Larry R Samons, Mason, OH (US);
General Electric Company, Cincinnati, OH (US);
Abstract
A process for identificaiton, evaluation and removal of microshrinkage of investment cast superalloy parts and parts produced by the process. Parts free of deleterious microshrinkage capable of longer life at existing stress levels or use at higher alternating stresses are produced by first subjecting the parts to hot isostatic pressing to eliminate nonsurface connected subsurface microshrinkage. Next, in order to expose near-surface microshrinkage microscopically connected to the surface, the parts are immersed in an acid solution for a time sufficient to uniformly remove at least about 0.005 inches of the original as cast surface. The exposed microshrinkage is evaluated for acceptability or removal by standard nondestructive techniques, such as liquid penetration evaluation.