Effect of Carbon Fibre Surface Treatment on Moisture Absorption and Interlaminar Shear Strength of Carbon Fibre/Epoxy Resin Composites

摘要

Carbon fibres surface treated to eight different levels of the standard treatment were moulded into unidirectional composites in an epoxy resin. The composites were immersed in boiling water or exposed to a hot humid environment (70C, 95% RH), and the water absorption, swelling and interlaminar shear strength were measured. The reversibility of these effects was studied initially by drying the composite at 70 C in a vacuum oven and further by repeated hygrothermal cycling. In general more moisture was absorbed for the lower levels of surface treatment where the bond between the fibre and matrix was weaker. Studies of reversibility showed that there was a greater probability of permanent damage for low fibre matrix bond strengths and for specimens immersed in boiling water.