Production of aluminum nano-composite reinforced by tungsten carbide particles via mechanical milling and subsequent hot pressing

Abstract

Abstract Mixtures of 5, 10, 20 and 30 wt.% of tungsten carbide powder and 7075 aluminum alloy powder were ball milled for 20 hrs to investigate the effect of percentages of the reinforcement on microstructural and mechanical properties of the produced composite. The milled powders were sintered in a hot press and analyzed using X-ray diffraction. The microstructure, physical and mechanical properties of the specimens were studied. Results showed that the milling process synthesized Al–WC composite powders in which crystallite sizes of the produced phases were in the nano-scale regime. Although the higher amounts of tungsten carbide increased bulk density of the sintered samples, the apparent density decreased. The increase in the amount of the tungsten carbide phase increased effectively the hardness of the sintered specimens, however, the ultimate tensile strengths showed an maximum value at 20 wt.% of the reinforcement phase.