埋炭条件下C-Si系材料高温物理化学变化过程  

High-temperature reaction process of C-Si system materials in immerged carbon powders

作　　者：祝洪喜[1] 易成雄[1] 邓承继[1] 白晨[1] 石生德[2] 

机构地区：[1]武汉科技大学耐火材料与高温陶瓷国家重点实验室培育基地,湖北武汉430081 [2]武汉钢铁股份有限公司硅钢厂,湖北武汉430082

出　　处：《武汉科技大学学报》2008年第4期364-368,共5页Journal of Wuhan University of Science and Technology

基　　金：国家自然科学基金资助项目(50772079);湖北省自然科学基金资助项目(2007ABA050)

摘　　要：以炭黑和单质硅为原料压制成试样,在埋炭条件下,分别于1 200,1 300,1 350,1 400,1 450,1 500℃下高温烧结,获得不同温度点合成样品。采用XRD分析技术研究试样的物相演变过程,从而对C-Si系原料在埋炭气氛反应过程中的物相变化和反应动力学机制进行研究。试验结果表明:试样中新生成的物相为SiC、石英相和方石英相,几乎没有Si3N4和Si2N2O相。其反应过程是:单质硅与O2生成SiO2、与C反应生成SiC、与CO反应生成SiC和SiO2;温度高于1 450℃时,SiO2又会与试样中剩余的C反应生成SiO和SiC。整个过程都伴随着方石英化过程。当温度高于1 450℃时,会发生硅的挥发。合成温度和原料配比是影响C-Si系原料合成产物的生成速率和生成量的重要动力学因素。Nine groups of samples made from carbon black and industrial Si at different ratios were fired in immerged carbon powders at six temperatures of 1 200, 1 300, 1 350, 1 400, 1 450, and 1 500 ℃, respectively. By means of XRD, the phase compositions of the sintered samples were analyzed, and the reaction dynamics of C-Si system materials in immerged carbon powders is explained. It is found that, there are SiC phase, quartz, and cristobalite in the samples yet hardly Si3N4 and Si2N2O phases. The reaction process is like this： SiO2 and SiC are produced from the reactions between Si and O2, Si and C, or Si and CO, respectively; when the synthesis temperature rises above 1 450 ℃, SiO and SiC phases are produced from the reaction between SiO2 and the rest C in the samples, and the loss of Si will take place. The sintering temperature and the starting material compositions are the key to controlling the synthesis speed and rate of the sintered samples.

关 键 词：C—Si系原料 埋炭 反应过程 

分 类 号：TQ110.3[化学工程—无机化工]