Tribological Behavior of M50-Sn-Ag-Cu Composites with Curved Microchannels

To overcome the poor tribological performance of M50 and widen its working range under high temperature, M50-Sn-Ag-Cu composites with curved microchannels (MCCs) and straight microchannels (MCSs) were prepared by Laser Additive Manufacturing Technology, respectively. Tribological properties of M50-based composites were studied. The results showed that MCCs had the better tribological performance. At 25 °C-15 N-0.2 m/s, compared with MCSs, the average friction coefficient of MCCs at the stable friction stage was reduced by 10.7%. In contrast to MCSs, MCCs had a wider operating temperature range than MCSs, and the average friction coefficient of MCCs was decreased by 23.4 at.% 350-450 °C. According to the simulation results, the lubricant expansion of MCCs was 1.56 times that of MCSs at 400 °C. The curved microchannels design makes the storage and formation capacities of the lubricating film be enhanced without weakening the bearing capacity of MCCs. The two-way opening design of the curved microchannels could reduce the stress concentration between lubricant and friction interface, hence ensuring the efficient precipitation of lubricant. The research work could have a guiding role for widening the temperature range of M50 composites and improving the reliability of high-end equipment bearing.