Synthesis of beta-SiC powder from alkoxide precursor and study of its sintering behaviour

AbstractIn this study, β-SiC powder was prepared using a pyrolysed spherical precursor derived from the hydrolysis mixture of phenyltrimethoxysilane and tetraethyl orthosilicate. Before the pyrolysed experiment, an alkoxide precursor was characterised using 29Si solid nuclear magnetic resonance, Fourier transform infrared spectroscopy and thermogravimetric analysis. The alkoxide precursor was heated at 1800°C for 4 h under an Ar atmosphere. To examine the pyrolysed residue after heat treatment, the sample was collected and analysed with X-ray diffraction. The X-ray diffraction results for the sample show diffraction peaks at ∼35, 60 and 73°, which correspond to the β-SiC phase. According to the results of chemical analysis, the SiC content of the powder that was prepared at 1800°C was determined to be 99·4%. The sintering behaviour of the prepared β-SiC powder was examined using B4C and C as sintering additives in the temperature range of 1900–2200°C.