Design of Fe–SiC–Cu–G Composite Alloy and Optimization of Graphite Contribution for High Sliding Speed Applications

The aims of the present research are to obtain the optimal chemical formulation for a Fe–SiC–Cu–G metal-matrix composite (MMC) to achieve maximum wear resistance, and also to evaluate the mechanical properties of the composite based upon introducing graphite into the formulation at optimal dosage for suiting the MMC for common brake mechanisms used in aircraft, locomotives, racing cars, etc. The composites were manufactured by using cold-pressing, sintering in an electric arc furnace with protective gas, and hot-pressing. Comparison of the obtained samples indicated that the hot-pressing was applied to obtain the optimal composite formulation. Then, the fracture surfaces of prepared composites were examined by scanning electron microscope. In addition, barium sulfate (BaSO 4 ) was used to enhance the wear resistance of the composite by increasing its friction coefficient during the wear. The optimal ratio of graphite in the composite was also determined. The optimal composite sample was composed of Fe-11Cu-6SiC-6.5G-6BaSO 4 . The results of wear, hardness, and density tests showed that adding the BaSO 4 and graphite into the Fe–SiC–Cu–G metal-matrix composite at optimal dosages improved the wear resistance of the MMC sample.