Surface characteristics of different cross-section carbon fibers and its effect on interfacial adhesion properties of composite

The surface characteristics of domestic kidney-section and circular section carbon fiber and foreign T300 circular section carbon fiber were physically and chemically characterized and analyzed by using the scanning electron microscopy (SEM), atomic force microscopy (AFM), specific surface area and pore volume test equipment (BET) and X-ray photoelectron spectroscopy (XPS). The interfacial adhesion properties of carbon fiber/epoxy composite were investigated. The surface topographic analysis results show that the specific surface area of kidney section carbon fiber is bigger than that of circular section carbon fiber, but its surface grooves is more shallow. The XPS analysis shows that the surface activity of kidney-section carbon fiber was a little higher than that of domestic circular section fiber, but obviously less than that of T300. The test results show that interfacial shear strength (IF-SS) and interlaminar shear strength (ILSS) of kidney section fiber/epoxy composite are close to those of T300/epoxy composite and higher than those of domestic circular section fiber/epoxy composite.