Low temperature behavior of carbon fiber/epoxy composites: matrix and fiber influences on cryogenic microcracking

摘要

The response of cross-ply carbon fiber I epoxy laminates to cryogenic cycling was evaluated through the use of model prepreg systems. The curing agent used, matrix backbone flexibility, and tensile modulus of the carbon fibers were varied to alter the properties of the composite material. Examination of the laminates after cycling provided insight into the mechanism and origins of thermal stress-induced microcracking. Matrix properties and fiber tensile modulus have been shown to have a significant impact on microcracking, with lower glass transition temperatures, higher fiber tensile moduli, and higher fiber coefficients of thermal expansion indicating an increased propensity for microcracking.