Curing behavior of a carbon fiber/epoxy prepreg and curing processing of laminates with microwave radiation

The curing behavior of a carbon fiber/epoxy prepreg under microwave radiation was investigated using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR), respectively. The carbon fiber/epoxy composite laminates were manufactured through microwave curing-vacuum bag molding process, and the existing overheating and broken issues of vacuum bags were studied. The results show that compared with thermal curing, microwave curing can significantly shorten curing time without altering molecular structure of the cured products. It seems that the size of the carbon fiber/epoxy prepreg influences its microwave curing characteristic. The problem of vacuum bag breakage, due to overheating in microwave curing of carbon fiber/epoxy composites, can be solved by controlling the microwave power, and the fabrication of the laminates with microwave radiation can be accomplished in about 60 minutes with more than 95% curing degree, indicating that microwave processing is shortened by more than half of curing time than conventional thermal curing (curing time more than 2h).