Accession Number : ADA303830

Title :   Hygrothermal Damage Mechanisms in Graphite-Epoxy Composites.

Descriptive Note : Contract rept.,

Corporate Author : LOCKHEED MISSILES AND SPACE CO INC PALO ALTO CA PALO ALTO RESEARCH LAB

Personal Author(s) : Crossman, Frank W. ; Mauri, R. E. ; Warren, W. J.

PDF Url : ADA303830

Report Date : DEC 1979

Pagination or Media Count : 154

Abstract : This report covers experimental and analytical studies of T300/5209 and T300/5208 graphite-epoxy laminates: (1) to determine the coupling between applied stress, internal residual stress, and moisture sorption kinetics, (2) to examine the microscopic damage mechanisms due to hygrothermal cycling, (3) to evaluate the effect of absorbed moisture and hygro- thermal cycling on inplane shear response, (4) to determine the permanent loss of interfacial bond strength after moisture absorption and drying, aid (5) to evaluate the three-dimensional stress state in laminates under a combination of hygroscopic, thermal and mechanical loads. Specimens were conditioned to equilibrium moisture content under steady exposure to 55 or 95% RH at 70 or 93 deg C. Some specimens were tested subsequent to moisture conditioning and 100 cycles between -54 deg C and either 70 deg C or 93 deg C. jg p4

Descriptors :   *DAMAGE, *MOISTURE CONTENT, *HUMIDITY, *GRAPHITE EPOXY COMPOSITES, SHEAR PROPERTIES, STRESSES, EXPERIMENTAL DATA, INTERFACES, WATER, COMPOSITE MATERIALS, LAMINATES, FINITE ELEMENT ANALYSIS, LOADS(FORCES), EQUILIBRIUM(GENERAL), STRENGTH(MECHANICS), CYCLES, MICROSCOPY, THREE DIMENSIONAL, RESPONSE, HEATING, RESIDUAL STRESS, BONDING, LOSSES, KINETICS, ABSORPTION, GRAPHITED MATERIALS, EPOXY RESINS, SORPTION, THERMAL STRESSES, DRYING, TRANSVERSE, MOISTUREPROOFING.

Subject Categories : Laminates and Composite Materials
      Physical Chemistry
      Mechanics
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE