Fire properties of carbon fiber reinforced polymer improved by coating nonwoven flame retardant mat for aerospace application

In this study, two types of carbon fiber reinforced polymer (CFRP) flame retardant composites, CFRP@Mat _EG-GF and CFRP@Mat _EG-GF-MW (EG, GF, and MW are the acronyms of expandable graphite, glass fiber and mineral wool, respectively), were prepared via compression molding, with expandable graphite-based mat incorporated at the surface of the CFRP. The results showed that compared with the control CFRP, both CFRP@Mat _EG-GF and CFRP@Mat _EG-GF-MW passed vertical burner test and 45° burner test according to FAR25.853. Moreover, the limiting oxygen index (LOI) values of both CFRP@Mat _EG-GF and CFRP@Mat _EG-GF-MW were increased, and the peak of heat release rate (PHRR) and total heat release (THR) were reduced. Besides, CFRP@Mat _EG-GF-MW had higher flame retardancy than CFRP@Mat _EG-GF . This was attributed to the formation of a more stable and dense carbon layer structure. The mechanical test results showed that the tensile strength of CFRP@Mat _EG-GF-MW was higher than that of CFRP@Mat _EG-GF .