Abstract
The Ti(3)SiC(2)TiSi(x) ceramic composite was synthesized in situ from a mixture of 3Ti:1.5Si:1.2C powders under pressures ranging from 2 to 5 GPa and temperatures of 1150 °C to 1400 °C. At medium and high temperatures (4-5 GPa and 1400 °C), Ti(3)SiC(2) dissolves into the cubic TiC phase. SEM analysis revealed that the high-pressure-produced multilayer structure of Ti(3)SiC(2) remained intact. The friction properties of Ti(3)SiC(2)-TiSi(x) composites combined with copper and aluminum were studied under both dry and lubricated conditions. After the break-in period, the Ti(3)SiC(2)-TiSi(x)/Al combination exhibited the lowest friction coefficient: approximately 0.2. In dry-sliding conditions, the friction coefficient varies between 0.5 and 0.8. The wear mechanisms for Ti(3)SiC(2)-TiSi(x) composites paired with aluminum primarily involve pear groove wear and adhesive wear during dry friction. Irregularly shaped aluminum balls accumulate in the pear grooves and adhere to each other. With increasing sintering pressure, the average friction coefficient of Ti(3)SiC(2)-TiSi(x) composites against Cu ball pairs first increases and then decreases. The wear rate of the samples did not vary significantly as the sintering pressure increased, whereas the wear rate of Cu balls decreased with increasing sintering pressure. The adhesive wear of the Ti(3)SiC(2)-TiSi(x) composite with its Cu counterpart is stronger than that of the Al counterpart. Abrasive chips of Cu balls appeared in flake form and adhered to the contact interface.