Effect of Post-thermal shock on Prolonged Sea Water aged GFRP Composite

The present investigation is an attempt of evaluating the suitability of glass fibre reinforced polymer composites to thermal shock treatments of various lengths of time subject to pre-immersion in sea water for 1 year. Mechanical properties like inter laminar shear strength (ILSS), stress at rupture, strain at rupture and modulus values are recorded by adopting 3-point bend test method. Mechanical properties show a general decreasing trend at higher durations of up and down-thermal shock exposure irrespective of showing initial nonequilibrium zig-zag trend. Glass Transition temperature (T_g) with respect to optimum durations of thermal shock treatment show considerable variation for the sample with minimum sea water immersion period. SEM fractographs of the thermally shocked specimens revealed the mode of failures like fibre pull out, fibre/matrix debonding, cusp formation indicating polymer crazing, matrix cracking, fibre breaking etc. (paper)