Prediction of long-term safe structural behavior of polymer-based composite systems

Conference · Sun Oct 01 04:00:00 EDT 1995

OSTI ID:109723

Cardon, A H; Bruggeman, M; Van Hemelrijck, D ^[1]; Zaoutos, S; Mitropoulos, Y ^[2]; Guedes, R ^[3]

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1. COSARGUB-VUB, Brussels (Belgium)
2. Univ. of Patras (Greece)
3. Univ. of Porto (Portugal)

Composite systems with a polymer phase exhibit anisotropic time dependent properties. The viscoelastic nature of the polymer phase is responsible for the global time dependent properties of the system, for the strong influence of temperature variations, moisture diffusion and other environmental effect,s and also for the internal stress transfers between elastic and viscoelastic phases if the authors assume perfect interface conditions. A structural component built up with polymer matrix composite elements has to be designed taken into account those time and environmental related effects. For the design of such a structural component in a way to obtain a safe residual behavior for a given life time after an imposed complex mechanical loading history, combined with environmental variations, the authors need information on the evolution of stiffness and strength properties of the basic component and on the possible changes of failure modes. Some recent experimental results on graphite-epoxy unidirectionally reinforced composite laminates, taken as basic material element, under different stress variations are presented. The use of those results for the prediction of the long term behavior will be discussed. An overview will be given of the needs for further and more general experimental results on different composite laminates in order to obtain a complete data basis necessary for residual strength and stiffness prediction. Those predictions has to be applied and compared with real time results on well defined composite structural components.

• OSTI ID: 109723
• Report Number(s): CONF-950521--; ISBN 1-56676-313-4
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BENDING
CARBON FIBERS
COMPOSITE MATERIALS
COMPRESSION STRENGTH
CREEP
DESIGN
EPOXIDES
FAILURES
INTERFACES
MATHEMATICAL MODELS
MECHANICAL PROPERTIES
MOISTURE
SERVICE LIFE
STRESSES
TEMPERATURE DEPENDENCE
TENSILE PROPERTIES
TIME DEPENDENCE
ULTRASONIC TESTING