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:
Sep. 04, 1990
Filed:
May. 16, 1989
Basil P Leftheris, Huntington, NY (US);
Robert C Schwarz, Dix Hills, NY (US);
Grumman Aerospace Corporation, Bethpage, NY (US);
Abstract
The method of caustics employs a laser for illuminating an extended crack in stock sheet metallic material. A shadow area image is generated which has geometrical parameters which may be measured and applied to the calculation of stress intensity factor (K.sub.I). The variation of the shadow shape in response to specimen loading provides signatures corresponding with the degree and direction of residual stresses in the material adjacent a hole formed in the material. By determining stress-intensity factors and stress-intensity distributions, a higher degree of quality control for sheet stock material becomes possible in addition to allowing the assembling of such material in directions that will best counteract anticipated destructive external forces.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile