Time-Dependent Environmental Behavior of Graphite/Epoxy Composites

摘要: Abstract : Experimental and analytical investigations have been conducted to determine the individual combined effects of temperature absorbed moisture on time-dependent mechanical response unidirectional cross- plied graphite-epoxy composite. Tensile creep was measured at room four elevated temperatures (up glass transition region materials) for dry specimens moisture-saturated 75% 95% relative humidity. Results were obtained two material systems: Narmco T300-5208 Hercules AS/3502. The stress levels used demonstrated be within range linear viscoelastic response. Superposition techniques compliance master curves from results condition, quasi-elastic conversion employed extract relaxation modules behavior. Expansional strains due measured. From principal properties, laminate predicted using time-stepped elastic analyses environments considered. Analytical procedures transient nonuniform conditions formulated. An method minimizing residual stresses during cure developed, sample present materials are presented. Observations recommended resulting these included in this final report.