EFFECT OF TEMPERATURE ON THE TRANSVERSE CRACKING BEHAVIOR OF CROSS-PLY COMPOSITE LAMINATES

This paper investigates temperature-dependent transverse cracking in c ross-ply composite laminates over a wide range of service temperatures . The graphite-reinforced polymer-matrix composites considered are bis maleimide X5260/G40-800 (BASF) and Avimid K3B/IM7 (DuPont) materials. Fracture toughness is measured over a range of temperatures from -50 d egrees C to 175 degrees C and is found to be temperature dependent. Ma trix cracking initiation is quantified experimentally using acoustic e mission polar backscattering, ultrasonic inspection, and edge replicat ion. Various modeling approaches are correlated with experimental resu lts. It is found that the shear-lag model and the energy release rate model provide upper and lower bounds on experimental results. The sign ificance of including temperature-dependent properties is demonstrated . (C) 1997 Elsevier Science Limited.