Accession Number : ADD012878

Title :   Non-Destructive Evaluation Method for Coated Carbon-Carbon Composites.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Crane,Robert L

Report Date : 28 Apr 1987

Pagination or Media Count : 3

Abstract : A non-destructive technique for detecting and repairing surface flaws in the silicon carbide oxidation resistant coating of a carbon carbon composite. The surface of the composite is treated with a test liquid consisting essentially of a carrier fluid, a particulate pigment and a finely divided borosilicate glass, or a mixture of silicon dioxide and boron oxide, containing 0.25 to 8 weight percent boron oxide. The treated surface is inspected for surface flaws. Any discovered flaws are repaired by heating the surface to cause the borosilicate glass to flow and heal the flaw. The composite is thereafter heated to a further elevated temperature to deplete the boron from the flaw-sealing glass.

Descriptors :   *PATENTS, *CARBON CARBON COMPOSITES, *PROTECTIVE COATINGS, *HEAT RESISTANT GLASS, NONDESTRUCTIVE TESTING, BORON, GLASS, BORON OXIDES, SILICATES, MIXTURES, SILICON DIOXIDE, SURFACES, LIQUIDS, FLOW, GLASS, HIGH TEMPERATURE, PARTICULATES, PIGMENTS, MATRIX MATERIALS, SILICA GLASS, SILICON CARBIDES, SURFACE PROPERTIES, FIBER REINFORCED COMPOSITES, HARDENING, DEFECTS(MATERIALS)

Subject Categories : Laminates and Composite Materials
      Coatings, Colorants and Finishes

Distribution Statement : APPROVED FOR PUBLIC RELEASE