Property enhancement of CFRP composites with different graphene oxide employment methods at a cryogenic temperature

In this study, graphene oxide (GO) was used to improve the mechanical properties of carbon fibre reinforced polymer (CFRP) composites at room temperature (RT) and cryogenic temperature (CT). It was found that GO could effectively improve the mechanical properties of CFRP composites at both temperature conditions as compared to pristine composites, particularly at CT due to its unique thermal response. Two approaches of employing GO into CFRP composites, either dispersing GO into epoxy matrix or coating it onto the surface of carbon woven fabric (CWF) were also investigated and compared. The results showed that GO devoted to a more significant improvement in the mechanical properties of composites when it was employed on the surface of CWF. It was also discovered that the flexural strength and modulus of CFRP composites were reduced at CT by 8.74% and 10.63% respectively, but the addition of GO would help restrict the degradation of matrix and limit the reduction to 1.15% and 2.09% respectively, and thus retain its enhanced mechanical properties.