Accession Number : ADA185899

Title :   Interface Effects on the Mechanical Properties of Ceramic Composites.

Descriptive Note : Annual rept. no. 2, 15 Jul 86-14 Jul 87,

Corporate Author : ROCKWELL INTERNATIONAL THOUSAND OAKS CA SCIENCE CENTER

Personal Author(s) : Marshall, D B

PDF Url : ADA185899

Report Date : Sep 1987

Pagination or Media Count : 78

Abstract : Macroscopic and microscopic mechanical properties of ceramic composites have been investigated. A fracture mechanics analysis was developed to evaluate the influence of residual microstructural stresses on the fracture toughness of composites that are reinforced by crack bridging mechanisms. The magnitude and sign of the toughening were found to be very sensitive to the details of the bridging mechanism and the criterion for ligament rupture. These results highlight the need for techniques to measure microscopic mechanical properties such as residual stresses, interfacial debonding and sliding resistance, and deformation and fracture of small reinforcements. Further analysis of an indentation fiber pushing technique that was developed previously under this contract for measuring fiber-matrix interfacial properties has enabled the technique to be used to measure residual stresses in individual fibers and to measure frictional sliding resistance in carbon fiber composites.

Descriptors :   *CERAMIC MATERIALS, *COMPOSITE MATERIALS, BRIDGES, CARBON FIBERS, CRACKS, DEFORMATION, FIBER REINFORCED COMPOSITES, FIBERS, FRACTURE(MECHANICS), INTERFACES, LIGAMENTS, MATRIX MATERIALS, MEASUREMENT, MECHANICAL PROPERTIES, MICROSCOPY, MICROSTRUCTURE, RESIDUAL STRESS, RESISTANCE, RUPTURE, SLIDING, TOUGHNESS, CROSSLINKING(CHEMISTRY), WHISKER COMPOSITES, MODELS

Subject Categories : Ceramics, Refractories and Glass
      Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE