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A mixture of SiO2, C, and Mg powders is mechanically milled in a planetary ball mill during different milling times of 60, 90, 120, and 150 min. The milled powders are then used in a self-propagating high-temperature synthesis (SHS) reaction to produce the Si–SiC composite. The thermal properties of the milled powders are determined by using differential scanning calorimetry and thermogravimetry. The chemical composition and microstructure of both as-synthesized products and as-leached powders are characterized by the x-ray diffraction analysis and scanning electron microscopy, respectively. The results show that an increase in the milling times of the mixture of the reactant powders has a significant effect on the thermal properties, diffusion processes, and SHS reaction mechanisms, as well as on the phase conversion and the final yield of the products. [ABSTRACT FROM AUTHOR]

Intermetallic tungsten silicide alloy WSi2–W5Si3 was successfully synthesized via magnesiothermic SHS reaction in the WO3–Si–Mg system. Equilibrium composition of combustion products was calculated by standard Gibbs energy minimization method and the combustion products were characterized by XRD, SEM, and EDX. The synthesized alloy had a density of 8.97 g/cm3 (96.4% of theoretical). The process can be readily recommended for practical implementation. [ABSTRACT FROM AUTHOR]