Influence of Ultrasonic Oxidation on Surface Properties of Carbon Fibers

In order to improve the binding performance between carbon fibers and resin matrix, the surface of carbon fibers was modified by ultrasonic oxidation. Surface morphology and structure of the carbon fibers before and after treating were analyzed by means of scanning electron microscopy and laser Raman spectrometer. The wettability of the carbon fibers and the binding performance with the resin matrix were investigated. The results show that there were more grooves on the surface of carbon fibers after ultrasonic oxidation, and the graphitization degree had a certain improvement. With the prolongation of treatment time, the content of acid functional group on the surface of carbon fiber increased, and the wettability of the carbon fibers with water was improved significantly. Compared with carbon fibers before treating, the interface shear strength between treated carbon fibers and epoxy matrix increased by 33%.