Interlaminar fracture toughness of carbon/epoxy composites laminates toughened by short carbon fiber

Abstract

Abstract In this paper, short carbon fiber (SCF) interlaminar toughened carbon fiber reinforced epoxy resin (CF/EP) composite laminates were prepared. The effect of SCF content on the mode II interlaminar fracture toughness ( G IIC ) and flexural properties of CF/EP composites was investigated. It was shown that the addition of SCF between the plies had an effect on the G IIC of the composites. When the SCF content was 10 g/m 2 , the G IIC increased from 1506.62 J/m 2 to 1995.6 J/m 2 , which improved by about 32.46%. When the content of SCF was 5 g/m 2 , the flexural strength and flexural modulus increased by 36.92% and 98.48%, respectively, showing the best performance. The toughening mechanism of SCF was observed by SEM images as SCF debonding and pulling out from the resin and SCF fracture. The present study was also compared with our previous study on short aramid fiber interlaminar toughened CF/EP composites, and the test data and SEM images of the two experiments were compared to analyze the effect of different short fibers on the interlaminar toughening effect, which provides some reference for the selection of interlaminar toughening materials.