Fabrication And Wear Resistance Of TiC_0.5/Cu（Al）Composites

Good properties make copper and copper alloy a wide range of applications. some weaknesses, however, make its application limited. Ceramic particles reinforced copper matrix composite materials are were known due to their promising properties, such as good electrical and thermal conductivity, high strength performance, good wear resistance and good corrosion resistance. The fabrication procedure, microstructure, strength performance and wear resistance of TiC0.5/Cu(Al) were investigatedDifferent TiC0.5volume fraction of TiC0.5/Cu(Al) composites were prepared by in-situ hot pressing at the high temperature of1150℃, using Ti2AlC and copper powders as raw materials. Raw materials was mixed by rotary drum type ball milling and high energy ball milling respectively before sintering. As shown in the results, Al of H2AlC dissolved and diffused into Cu, Ti2AlC decomposed and turned into TiC0.5, and a small amount of AlCu2Ti phase was found in the composites whose milling method was rotary drum type ball milling, the amount of AlCu2Ti phase become much more with the increase of TiC0.5volume fraction. Due to high energy ball milling method, AlCu2Ti phase generated in the composites finally disappeared, fine TiC0.5particle homogeneously distributed in the matrix.The result from strength performance test is shown that flexural strength sharply decreases, but Vickers hardness slightly increases, and brittle feature was observed in the fractographs as the TiC0.5content increases from27%to34%. Compared to rotary drum type ball milling method,27%TiC0.5/Cu(Al) composites with high energy ball milling shows a4percent increase in flexural strength and a16percent decrease in Vickers hardness, meanwhile34%TiC0.5/Cu(Al) composites with high energy ball milling shows a17percent increase in flexural strength and a7percent decrease in Vickers hardness.27%TiC0.5/Cu(Al) composites with high energy ball milling has quite high flexural strength (981MPa) and Vickers hardness (2.43GPa).According to the result from wear test, if TiC0.5volume fraction is less than20%, TiC0.5/Cu(Al) composites have poor wear resistance. However,27%TiC0.5/Cu(Al) and34%TiCo.5/Cu(Al) composite shows a good wear resistance thanks to the black thin film above the wear surface, with all the wear rates less than5.0×10-6mm3/N·m whatever the wear condition is. EDS of the black thin film shows that the film contains several elements like T1、Cu、(Al)、Fe and O, gives the composites more lubrication and protection. Even if some local damages and exfoliations of thin film occur in27%TiC0.5/Cu(Al) and34%TiC0.5/Cu(Al) composites, the materials still have pretty low wear rates.