1989 Volume 38 Issue 429 Pages 637-643
Fracture toughness of GFRP composite materials has been studied mainly from the view point of the effects of test temperature and specimen size at temperatures ranging from 300K to 4K. The CT specimens with cut slits of prescribed depth and width were used.
The fracture toughness of the GFRP specimens increased linearly with lowering test temperature from 300K to 77K. The effect of the slit width on fracture toughness was found to be the tendency of fracture toughness converging to a constant value below 0.2mm slit width. The plane stress state was attained when the ratio (B/W) of thickness (B) to width (W) of the specimens was below 0.2, accompanied with the incrase of fracture toughness. Also the whitening tendency of the tear crack portion of the GFRP specimens in the tear test became clearer as the test temperature decreased.
