Transactions of the INDIAN CERAMIC SOCIETY Vol. 48 1989
Reaction Sintering Studies of Silicon Carbide
S. RAMANATHAN, RAM PRASAD AND C. K. GUPTA
Pages : 107-110
DOI : 10.1080/0371750X.1989.10822959
Abstract
In reaction sintering of siUcon carbide, newly formed grains bind
the already existing grains in a compact of silicon carbide and
carbon mixture under heating in an atmosphere of silicon vapour.
Powders of silicon carbide were prepaa-ed and characterized for
specific surface area, average particle size and size distribution. The
compaction characteristics of the mixtures of different silicon carbide
and carbon powders and the optimum compaction pressures for
bringing about proper "sUiciding" (reaction of silicon vapour and
particulate carbon) were studied and evaluated. SUiciding studies were
carried out in the temperature range of l500°-2000°C in argon
atmosphere at pressures from 760 torr to 10-1 toiT. The sintered
specimens were characterized for bulk density by water displacement
method and completion of reaction by X-ray diffraction. Sintered
densities of the order of 80-85% of the theoretical value could be obtained
by optimizing argon partial pressure and increasing the reaction
temperature to 2000°C. XRD investigations revealed that a small
amount of free silicon was always left behind in the matrix.
