Characterization of Copper MMC Reinforced with SiC and Graphite in Equal Proportion Made by the Powder Metallurgy Route

Abstract

Powder metallurgy is playing a very important role in the manufacturing industry. In this research, an attempt is made with copper Metal Matrix Composites (MMC) reinforced with an equal proportion of Silicon Carbide (SiC) and graphite powders. The powders are taken in such a way that the reinforcement weight percentage varies from 0 to 10%. The materials are fabricated through the powder metallurgy route. The powder mixtures are blended and then compacted with a uniaxial pressure of 500 MPa to make the green compacted composites with different compositions. The dimensions of all samples are 25 mm x 16 mm x 16 mm, with an average weight of 40 g. Compacted green samples are sintered by the inert gas sintering process. Sintering is performed at 8000C in an inert argon gas furnace for 120 minutes for all the samples. The obtained samples are made suitable for different tests like porosity, the Vickers hardness test, the wear test, Raman spectroscopy, Scanning Electron Microscopy (SEM), and Energy Dispersive X-Ray (EDX) Analysis. From the values obtained from the hardness test, it is observed that for all MMCs, the minimum value is obtained at Cu-4% (SiC+Gr) and the maximum value at Cu-8% (SiC+Gr), and in between these percentages of composition, there is a little bit of an increase and decrease in values. Wear test results give the maximum wear rate at Cu-4% (SiC+Gr) and the minimum wear rate at Cu-8% (SiC+Gr). Raman spectroscopy test results are given the calculations of Full Width at Half Maximum (FWHM), depth of incident, absorbance, and Id/Ig values, and they are better at 8% of SiC+Gr, which gives the indication of good bonding between molecules of the powder particles. Image analysis is performed using optical microscopy, SEM, and EDX. The microstructures were revealed in such a way that there was good correlation between the properties at different compositions.