Determination of the purity of silicon carbide by infrared absorption

Study the silicon carbide content in silicon carbide powder by high frequency infrared carbon sulfur analyzer. The parameters, such as pretreatment conditions of the sample, sampling, accelerator, blank value, comparative level, precision are determined through a series of test conditions, then the method for the detection of silicon carbide content in silicon carbide samples is established. When the sample is 0.03 g, placed at 750 ℃ in a muffle furnace for 2 h, then cooling the temperature, addition of 1.5 g tungsten, 0.5 g iron, 0.3 g tin, analysis power is 70%, analysis time is 50 s, comparative level is 2.00%, the precision is better than 10%. Using calcium carbonate standard substance for recycling, the recovery is 85% ∼ 120%. (authors)