Study on the Reaction Parameter as SiC Powder Preparation by Combustion Synthesis

摘要

Silicon carbide was synthesized by a combustion synthesis process using exothermic mixture of Mg and (-C_2F_4-) as an activated additive, silicon and carbon. Silicon carbide was synthesized differently with the addition of the activated additive. Especially, with 25 wt. percent of the additive, better conversion of Si to SiC was obtained. For the types of carbon, it was observed that carbon black and activated carbon showed better reactivity than graphite. In regard of the molar ratio change, when the molar ratio of silicon vs. carbon was 1:2, Si was converted to silicon carbide completely. Among the products, MgF_2 was entirely removed by leaching for 4 hrs. at a mixture of 10 vol. percent (HNO_3 + HF) +90 percent water.