Fabrication and high temperature tribological properties of WC reinforced W-Cu composites

In this study, WC doped W-Cu composites with high hardness and excellent tribological properties were prepared using hot pressing sintering with Cu coated W composite powders. Friction and wear behaviors of W-Cu-WC composites and W-Cu composites against Si3N4 balls at room and high temperatures (e.g., 25 degrees C, 700 degrees C and 900 degrees C) were investigated using a ball-on-disk high temperature tribometer in vacuum. Results showed that the Vickers hardness of WC doped W-Cu composites (245 HV) was relatively higher than that of the W-Cu composites. The specific wear rate of WC doped W-Cu composites was lower than that of the W-Cu composites in the temperature range of 25-900, and that at 700 degrees C (56.3 x 10(-5) mm(3)/Nm) was an order of magnitude lower than that of the W-Cu composites. The wear resistance of W-Cu composites doped with WC particles was dramatically improved in vacuum. The dominant wear mechanisms of W-Cu composites were abrasive wear, adhesive wear and delamination at various temperatures, whereas the dominant wear mechanisms of W-Cu-WC composites were abrasive wear and delamination at various temperatures.