Experimental Investigation on the Correlation between Damage and Thermal Conductivity of CFRP

Abstract

By measuring the change in stiffness and thermal conductivity along with damage growth, the interaction of damage and thermal conductivity of the laminate is investigated. A quasi-isotropic carbon reinforced composites is subjected to tension – tension fatigue loading and an in-situ DIC technique at high magnification is used to capture the initiation and propagation of micro cracks at different cycles. The thermal conductivity is measured using a modified transient plane source technique. The thermal conductivity, modulus of elasticity and the full-field strain across the thickness, are evaluated. The study has elucidated the gradual growth of matrix cracking and its transformation to inter-ply debonding up to fiber breaking. The growth of local cracks and its corresponding influence on the change in thermal conductivity at different fatigue cycles are acquired. Thereby, the effect of local damages on the heat flow and thermal conductivity of the laminate is understood. Similarly the change in modulus of elasticity with the crack growth is elaborated. Finally an explicit correlation between the degradation of thermal conductivity and modulus of elasticity is described.