Accession Number : ADP004980

Title :   Restrained Thermal Growth of Carbon Phenolics and Its Relevance to the STS-8A Event,

Corporate Author : SOUTHERN RESEARCH INST BIRMINGHAM AL

Personal Author(s) : Koenig,J. R.

Report Date : DEC 1984

Pagination or Media Count : 10

Abstract : The across-ply response of carbon phenolics under uniform rapid heating (10-30 deg/sec) has been measured under varying degrees of across ply restraint, particularly with the boundary condition such that across-ply strain = 0. These tests have been conducted on various carbon phenolics. The response shows a rather dramatic difference from that predicted from E alpha Delta T using the measured free expansion, which has previously been attributed to an effect of load on the free expansion giving a different, lower, effective expansion. A dramatic failure mode is seen in some materials. A hypothesis is presented, which accounts for this, both the change in response and the failure, based on a micromechanical model of the material. The correlation of these tests and model with the vent seen in STS-8A is shwon and the implications of this response on carbon phenolic design are discussed.

Descriptors :   *CARBON PHENOLIC MATERIALS, DEFORMATION, THERMAL EXPANSION, RESTRAINT, FAILURE(MECHANICS), LOADS(FORCES), LAYERS, MODEL TESTS, CARBON YARN, TENSILE PROPERTIES, DIRECTIONAL, MATHEMATICAL PREDICTION, ROCKET NOZZLES, SOLID PROPELLANT ROCKET ENGINES

Distribution Statement : APPROVED FOR PUBLIC RELEASE