Synthesis and characterization of Al-Cu-Mg system reinforced with tungsten carbide through powder metallurgy

This paper deals with the processing and characterization of an alloy based on an Al-Cu-Mg system, which was reinforced with tungsten carbide through powder metallurgy and a sintering process. The effects of milling time (0, 3, and 5 h) and sintering temperature (450, 500, and 550 degrees C) on the phase transformations and crystalline properties (lattice parameter, microstrains, and crystallite size) were investigated. X-ray diffraction, scanning and transmission electron microscopy, and Vickers microhardness measurements were used to examine the structures, microstructures, and mechanical properties of the composites. Results showed that the milling process enables homogeneous dispersion of the reinforcement material in the Al-Cu-Mg matrix, allowing the fabrication of a novel Al-Cu-Mg/WC composite. Strong particle-matrix interface bonding was achieved owing to a diffusion gradient formed between the particles and matrix. The best performance, in terms of reinforcement capacity and microhardness, was obtained with samples milled for 3 h and sintered at 450 degrees C, which exhibited low porosity, homogeneously dispersed reinforcement material, and strong bonding at the interface between WC and the Al-Cu-Mg matrix.