Effects of plasma treatment on properties of carbon fiber and its reinforced resin composites

The influence of plasma treatment on the wettability of carbon fiber was studied using the vacuum assisted resin transfer molding (VARTM) process. The influence of plasma treatment on the mechanical properties of carbon fiber-reinforced polymer (CFRP) composites, including interlaminar shear strength and tensile properties, were investigated. The carbon fiber surface chemistry analysis was carried out by Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS). Results showed that low-temperature plasma treatment had little effect on the surface morphology of the carbon fiber; however, it changed the chemical surface state of the carbon fiber, which contributed to enhance the wettability of the carbon fiber by increasing the perfusion speed of the resin to be more than two times of the original speed. The fiber wettability improvements are of great significance to the preparation of the CFRP composite by the VARTM process. Compared to untreated carbon fiber, the plasma treatment caused an acceptable decrease in tensile properties and offered an increase in the interlaminar shear strength of the CFRP composite. Low-temperature plasma treatment played an important role in the effective preparation and application of the CFRP composite.