Tribological behavior of silicon nitride reinforced polycarbonate nanocomposites

Abstract

AbstractPolycarbonate (PC) matrix nanocomposites containing 0–20 vol.% nanosize silicon nitride (Si3N4) particles have been prepared by solution mixing method. A combination of X‐ray diffractometry and transmission electron microscopy has been used to characterize phase purity and morphology of Si3N4 nanoparticles. The prepared nanocomposites have been investigated for density, microstructure, microhardness, and tribological behavior. Density and microhardness have been found to increase with increasing volume percent of nanoparticles. The experimental values of density of composites fall close to those of theoretical values predicted from the rule of mixtures thereby suggesting that prepared nanocomposites were nearly pore free. The maximum improvement of microhardness of 189% has been found for nanocomposite with 20 vol.% Si3N4 particles as compared to neat PC. Experimental data of microhardness correlated well with the modified rule of mixtures (with strengthening efficiency factor β = 0.09). Scanning electron micrographs indicated well dispersion of nanoparticles in PC matrix. Tribological (friction and wear) behavior have been evaluated using pin‐on‐disc method. It has been found that 20 vol.% nanocomposite exhibited lowest friction coefficient and highest (~ 68%) wear resistance as compared to neat PC. Based on the results, the prepared nanocomposites are suggested to be used in cams, gears, boat and pump impellers.