Fabrication and characterisation of copper –tungsten composites by mechanical alloying and sintering methods

Currently, among the commercially valuable metal-based materials, copper and copper-based composites are important for different applications due to their superior properties. Due to their high electrical and thermal conductivity and good corrosion resistance, copper and copper-based composites are widely used in thermal and electronic applications such as electronic packaging, electrical contacts and welding electrodes. In this study, copper powders reinforced with different proportions of tungsten were subjected to both mixing and high-energy milling processes. Compression behaviour of the produced composite powders was investigated by applying different pressures with a uniaxial cold press. The sinterability behaviour of the samples compressed with different compress pressures was investigated as a result of sintering at 850 °C for 2 hours. The samples compressed with the selected compression pressure were compared by sintering at different temperatures and times. Microstructural characterization of the fabricated composites was carried out by X-ray diffraction, optical microscopy and scanning electron microscopy. The mechanical properties were determined by Vickers microhardness and wear tests. Finally, the electrical conductivity of the composites was investigated using an electrical conductivity probe. According to the results, the highest hardness (110 HV) and good wear rate (0.54±0.09 x10-3 mm3/Nm) values were shown by the copper composite sample containing 20% W in the mechanically alloyed sample.