Abstract:For the application demand of composites under liquid N2 temperatureꎬ several carbon fabric/ epoxy
composites have been prepared by RTM process.The flexural propertiesꎬ compression strengthꎬ interlamniar shear
strengthꎬ and impact strength at 80℃ꎬRT and -196℃ have been tested.GⅠC and GⅡC at RT have also been tested.
Compared with room temperatureꎬ the flexural strengthꎬ compression strength and impact strength of M40 ̄level braid ̄
ing fabric/ R608-1 composites under -196℃ obviously increasedꎬ while the effect of cryogenic temperature on the
modulus of composites was small. The effects of resin toughness on the strength and modulus of composites were smallꎬ
while the effects of carbon fiber on the strength and modulus of composites were large. In any caseꎬ toughness of resin
matrix and variety of carbon fabric could not change the trend of mechanical properties vs temperature. Besidesꎬ both
toughness of resin matrix and variety of carbon fabric could affect the interlaminar fracture toughness of composites.
And high ̄toughness resin matrix could improve the interlaminar fracture toughness more obviously. The GⅠC and GⅡC
of M40 ̄level braiding fabric/ R608-2 composites was as high as 868 J/ m2 and 2 750 J/ m2ꎬrespectively. Howeverꎬ the
Tg of composites with high ̄toughness resin matrix was relatively low.