Synthesis of SiC matrix in ceramic matrix composite from Gaseous SiO using Ni

Abstract

Silicon carbide (SiC) can be synthesized from gaseous silicon monoxide (SiO) and toluene vapor in the presence of a nickel (Ni) component, in the form of Ni or Ni oxide form at a temperature of 1400 °C with very high catalytic activation. With the aid of the catalytic effect, SiC can be formed from continuously supplied gaseous SiO and toluene vapor such that: fibrous SiC is formed in a free space containing a Ni component having a particle size of several micrometers; a dense SiC body is formed from a SiC powder compact carried with a Ni component, and particularly, SiC matrix is formed between SiC filaments of SiC fabric when a SiC powder carried with a Ni component is placed within the SiC fabric. The latter two cases are believed due to SiC formation to embed the small spaces between SiC particles or filaments from gaseous SiO and toluene vapor at the positions of Ni component spread substantially over the entire surface of SiC particles, in which the outer surface of the SiC powder compact or SiC fabric is far from blocking since the Ni component is not placed at the outer surface. Accordingly, this study proposes a novel chemical vapor infiltration process for creating the SiC matrix in a ceramic matrix composite.