Physico-mechanical and tribological properties of Cu/h-BN nanocomposites synthesized by PM route

Manufacture of self-lubricating net-shapes composites has become an important issue in recent years due to their unique tribological properties which make them suitable for a wide variety of advanced applications. In this work, nano-copper with 2.5, 5, 7.5 and 10 wt.% of hexagonal boron nitride (h-BN) composites were prepared by powder metallurgy (P/M) technology. These mixtures were uniaxially pressed by applying different loads (300-1200 MPa) and sintered at a temperature range of 900-1000 degrees C. The outcomes indicate that the relative green density is directly proportional to the applied load and inversely proportional to the content of h-BN. Cu/h-BN composites formed under 700 MPa and sintered at 950 degrees C for 2 h recorded the highest relative density, hardness and compression strength. They are exhibited the lowest electrical resistivity, wear rate and coefficient of friction. These results attributed to h-BN characteristics such as low density, high dielectric constant and lubricity. (C) 2014 Elsevier B. V. All rights reserved.