Friction and Wear Performance of 3D-Printed Graphite/SiC Composites with Different Graphite Layer Deflection Angles

Abstract

This study explores the combination of selective laser sintering 3D printing of graphite with the melt infiltration of silicon to produce graphite/SiC self-lubricating composites featuring graphite layers with varying deflection angles. The findings suggest that the deflection angle of graphite layers plays a crucial role in influencing the friction and wear characteristics of the composite materials. Specifically, graphite layers with deflection angles below 45° result in surface crushing and the stacking of lubricating films, leading to a noticeable ploughing effect. Conversely, deflection angles exceeding 60° cause, the graphite layers to break easily within the substrate, making it challenging to consistently provide lubrication over an extended period, consequently resulting in severe abrasive wear. In the range of 45° to 60° deflection angles, the graphite layers exhibit a tendency towards sliding dispersion, facilitating the dynamic filling of surface pits and scratches. This behavior contributes to the demonstration of low friction coefficients (ranging from 0.11 to 0.14) and exceptional wear resistance (measured at 3.23 to 3.79×10-6mm3/Nm).