Effect of molding process on tribological characteristics of friction materials based on resin

Resin transfer molding (RTM) and hot-pressing molding (HPM) were used to prepare phenolic resin matrix composites reinforced by carbon fiber. The tribological properties of the materials were tested using a MS-T3001-type friction and wear tester. A scanning electron microscopy and three-dimensional laser microscopy were used to analyze the superficial microstructure of the friction materials. Furthermore, a comparative analysis was employed to investigate the influences on the tribological properties by two types of material-forming processes. Results indicate that the friction coefficient decreases with increased relative sliding speed and workload. For the RTM friction material, the main form of wear is adhesive wear and fatigue wear, the coefficient of friction is 0.075-0.120, and the wear rate is 7.5×10^-8 g·N^-1·m^-1. In contrast, for the HPM friction material, abrasive wear is the main form of wear, and the friction coefficient and wear rate are 0.085-0.130 and 1.5×10^-8 g·N^-1·m^-1, respectively.