Development and Mechanical Characterization of Copper-Hexagonal Boron Nitride Metal Matrix Nanocomposites Using Powder Metallurgy Route

In the present study, the effect of hexagonal boron nitride (hBN) on the mechanical properties and the wear behavior of the Cu-based metal matrix nanocomposites is investigated. Cu-x wt.% hBN (x = 1, 3, 5 and 7) nanocomposites were developed by the powder metallurgy (PM) route. Commercially available hBN was ball milled for up to 20 h in a high-energy planetary ball mill in order to exfoliate the hBN. The exfoliated hBN was characterized using various techniques in order to determine its structure and morphology. The various Cu-x wt.% hBN powder mixtures were cold compacted and sintered at 850 °C for 2 h in Ar atmosphere. All Cu-x wt.% hBN nanocomposite showed improved hardness and better wear resistance as compared to the pure Cu sample developed under similar conditions. The Cu-1 wt.% hBN showed improvement of hardness of ~ 40% and lowest wear rate. Maximum relative density and highest hardness was observed in the case of Cu-1 wt.% hBN nanocomposite of ~ 83.15% and ~ 69.33 HV, respectively. The 2D hBN nanofiller was found to be very effective in improving the mechanical properties and the wear resistance of the Cu-based nanocomposites. Free vibration analysis of the Cu-hBN nanocomposites circular plate showed that Cu-1 wt.% hBN nanocomposite has higher natural frequency among all the Cu-hBN nanocomposites.