Accession Number : ADA307037

Title :   Friction and Wear of Carbon-Graphite Materials for High-Energy Brakes.

Descriptive Note : Technical note,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CEN TER

Personal Author(s) : Bill, Robert C.

PDF Url : ADA307037

Report Date : JUN 1975

Pagination or Media Count : 30

Abstract : Caliper-type brake simulation experiments were conducted on seven different carbon-graphite material formulations against a steel disk material and against a carbon-graphite disk material. The effects of binder level, boron carbide (B4C) additions, graphite fiber additions, and graphite cloth reinforcement on friction and wear behavior were investigated. Reductions in binder level and additions of B4C each resulted in increased wear. The wear rate was not affected by the addition of graphite fibers. Transition to severe wear and high friction was observed in the case of graphite-cloth-reinforced carbon sliding against a disk of similar composition. This transition was related to the disruption of a continuous graphite shear film that must form on the sliding surfaces if low wear is to occur. The exposure of the fiber structure of the cloth constituent is believed to play a role in the shear film disruption.

Descriptors :   *AIRCRAFT, *FIBER REINFORCED COMPOSITES, *BRAKES, *WEAR RESISTANCE, *SLIDING FRICTION, SHEAR PROPERTIES, GRAPHITE, CARBON FIBERS, STEEL, LININGS, FABRICS, BORON CARBIDES, BINDERS, SLIDING.

Subject Categories : Aircraft
      Laminates and Composite Materials
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE