Manufacture of Copper/Silicon Carbide Foam Ceramic Dual Continuous Phase Composite Material and Research on Its Frictional Properties in Harsh Environment

Increasing requirement in the speed and load of high-speed rail (HSR) command wear-resistant materials of brake pad to work under harsh environment, especially at elevated temperature and high pressure. Ceramic-metal composite materials are often introduced as a solution due to the dual advantages of high hardness and toughness. However, considerable amount of damage and loss in wear process cause the demand which to improve its wear resistance in harsh environment. Here, for the first time, silicon carbide (SiC) foam ceramics with high thermal conductivity and high hardness was involved and combined with copper by squeeze casting to fabricate the composite material which can withstand harsh environments. Tribological performance evaluation in terms of performance coefficient of friction, wear rate and emergency brake testing are carried out on the dry friction material performance testing machine and friction brake testing machine. Characterization of properties showed that SiC foam ceramic enhanced the heat resistance and wear loss, it has better coefficient of friction in application of high speed and load, the wear rate is only 11.4% of commercial copper-based powder metallurgy brake pads. The foam ceramic/Cu shown excellent wear resistance when heated to a temperature exceeding 800°C during braking in high speed.