Elastic moduli and interlaminar shear strength of a bidirectional carbon/carbon composite after heat treatment

A bidirectionally laminated carbon/carbon composite was heat treated (graphitized) at three different temperatures (1800, 2100, and 2400 deg C). The Young's modulus, E sub 11 , the intralaminar modulus, G sub 12 , and the interlaminar shear modulus, G sub 13 , were measured by a resonant beam method for the three modifications. It is shown that an increase in the graphitization temperature leads to an increase in the Young's modulus and a decrease in the interlaminar shear modulus. The intralaminar shear strength shows a maximum for the material heat treated at 2100 deg C and increases with increasing testing temperature.