Don S Box

US Patent:

59027568, May 11, 1999

Filed:

Jul 25, 1996

Appl. No.:

8/690404

Inventors:

Elsid I. Aly - Grand Prairie TX
Don Michael Box - Hurst TX
James Eugene Littlefield - Arlington TX

Assignee:

Northrop Grumman Corporation - Los Angeles CA

International Classification:

B32B3/10

US Classification:

442239

Abstract:

The present invention is a fiber reinforced ceramic matrix composite substrate with an integrated ceramic topcoat layer. The composite substrate is prepared by laminating a preceramic polymer impregnated fiber cloth, curing the laminate, and pyrolyzing the resulting substrate to an initial state. The composite substrate is re-infiltrated with the preceramic polymer, cured, and pyrolyzed to an initial densification level. The topcoat layer is then integrated with the composite substrate by applying transition plies to an exterior surface of the composite substrate, forming a particulate slurry from a ceramic powder and the preceramic resin, and applying the particulate slurry to the transition plies. The transition plies-particulate slurry layup on the composite substrate is autoclave cured and pyrolyzed. The composite substrate is then re-impregnated with the preceramic resin matrix material, cureclave cured, and step pyrolyzed to a desired densification level.