Journal of Materials Science, Vol.30, No.13, 3475-3482, 1995
Thermochemical Synthesis and Characterization of Nanostructured Chromium Silicide and Silicon-Carbide Composite-Materials
Nanostructured chromium silicide/silicon carbide in the form of composite powders have been synthesized from water-soluble precursors by a spray-dry and thermal conversion process. Two materials compositions were investigated to provide insight into the relation between the initial precursor composition and the composition of the synthesized nanostructured materials. The multiphase materials that were produced contain (i) cubic beta-SiC and hexagonal Cr5-XSi3-YCX+Y(CT5Si3CX). A systematic study of the chemical and structured nature of these materials during and after processing was carried out using thermogravimetric analysis, differential thermal analysis, inductively coupled plasma spectrometry, Fourier transform-infrared spectroscopy, and X-ray diffractometry analysis. The calculated average grain size is around 20-80 nm. Microstructure observation using scanning electron microscopy and transmission electronmicroscopy revealed a distribution of nanoparticles with dimensions in the range 10-100 nm. This is in agreement with the precalculation from an analysis of X-ray line broadening.
Keywords:POWDERS