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. 03, 2019
Filed:
Mar. 25, 2015
Lockheed Martin Corporation, Bethesda, MD (US);
Suraj Prakash Rawal, Littleton, CO (US);
William H. Willcockson, Morrison, CO (US);
Wei Shih, Yorba Linda, CA (US);
Lockheed Martin Corporation, Bethesda, MD (US);
Abstract
Laminated carbon-carbon composites can be used as an ablative material, but they are often prone to delamination under thermally induced interlaminar shear and tension. Graded carbon-carbon composites with a sacrificial or ablative layer that is integral with one or more underlying layers and not fully dense can address these issues and provide other advantages. Such graded carbon-carbon composites can include a densified base layer containing a first portion of a carbonaceous matrix, and an outer ablative layer that is integral with the densified base layer and contains a second portion of the carbonaceous matrix. The carbonaceous matrix in the densified base layer has a first porosity, and the carbonaceous matrix in the outer ablative layer has a second porosity that is higher than that of the densified base layer. Methods for forming graded carbon-carbon composites can include heating a partially densified base layer and a carbonaceous matrix precursor above a carbonization temperature.