Mechanochemical synthesis of nanostructured SiO2-SiC composite through high-energy milling

Under ambient conditions, silica (SiO2) and graphite (C) were milled in a ring mill at up to 18 000 s, followed by heat treatment at 1000 degrees C. A SiO2-SiC nanocomposite with a ratio of 86.3:13.7 was obtained. The formation of an amorphous phase in the powder, the low degree of long-range order in the remaining crystalline particles, the large grain boundaries associated with the ultrafine crystallites, the high internal strain in the remaining crystalline SiO2, the ultrafine particle size, and the intimate mixing of reactants increased the reaction kinetics and reaction driving force for the SiC phase in the nanocomposite. (C) 2010 Elsevier B.V. All rights reserved.