Effect of milled B4C nanoparticles on tribological analysis, microstructure and mechanical properties of Cu-4Cr matrix produced by hot extrusion

In this paper, the dry sliding wear and friction behavior of Cu-4Cr-xB4C nanocomposites produced by powder metallurgy by varying the proportions of boron carbide viz. (x = 0, 4 and 8 wt.%) were studied. Die set assembly was preferred for making green compacts using a compression testing machine. The sintered compacts were hot extruded at 600 °C to reduce the porosity and to attain preform density of 92%, thereby improving the hardness and wear resistance. Scanning electron microscope (SEM) and X-ray diffraction were used to characterize the powders. Vickers hardness tester was used to evaluate the hardness of different compositions. Pin-on-disc instrument was used to find out the wear behavior of the composites. It was found that the wear loss and friction coefficient increased with an increase in applied load and sliding distance for all the compositions. The wear mechanisms which could be interpreted with SEM analysis of the nanocomposites were also studied.