镁热自蔓延法制备SiC工艺与过程的研究  

Process and Procedure of SiC Preparation by Magnesiothermic Self-propagation Method

作　　者：闫基森 刘凯旋 刘等卓 解芳[1,2] 华细金 彭银利 邱玉江[1,2] 陈玥含 王辛巳 YAN Jisen;LIU Kaixuan;LIU Dengzhuo;XIE Fang;HUA Xijin;PENG Yinli;QIU Yujiang;CHEN Yuehan;WANG Xinsi(Henan Province Engineering Research Center of Additive Manufacturing Aeronautical Materials,Nanyang Institute of Technology,Henan Nanyang 473004,China;Nanyang Key Laboratory of Additive Manufacturing Technology and Equipment,Nanyang Institute of Technology,Henan Nanyang 473004,China;Department of Engineering,University of Exeter,Exeter EX44QF,UK)

机构地区：[1]南阳理工学院河南省增材制造航空材料工程研究中心,河南南阳473004 [2]南阳理工学院南阳市增材制造技术与装备重点实验,河南南阳473004 [3]埃克塞特大学工程系,埃克塞特EX44QF,英国

出　　处：《精密成形工程》2025年第4期122-128,共7页Journal of Netshape Forming Engineering

基　　金：国家自然科学基金(52201044);河南省自然科学基金(252300421563);南阳市基础与前沿研究项目(24JCQY032);河南省高等学校重点科研项目(25B450001,25A460024,25B130003,24B460015);南阳理工学院大学生科研基金(2023-139)。

摘　　要：目的研究镁热自蔓延工艺制备SiC粉体过程中物相的演变规律以及有机碳源的反应机理。方法采用镁热自蔓延合成法,以SiO_(2)、Mg粉和葡萄糖(C_(6)H_(12)O_(6))为原料,探究镁粉和葡萄糖的添加量对制备SiC粉体的影响规律。结果热力学分析结果表明,在C_(6)H_(12)O_(6)-SiO_(2)-Mg体系中,随着温度的升高,生成SiC反应的吉布斯自由能增大,同时体系内杂质含量上升,不利于SiC的合成。实验数据表明,Mg粉添加量的增加导致反应产物中Mg_(2)Si相的衍射峰强度逐渐增强,而SiO_(2)相的衍射峰强度减弱;葡萄糖添加量的增加则使Mg_(2)Si相衍射峰强度减弱,SiC产物的收率呈现先增后减的趋势。经HF溶液酸洗处理后,产物为单相SiC。结论在葡萄糖过量30%(质量分数)与镁粉过量80%(质量分数)的条件下,SiC的收率达到最优,为51.9%。通过Freeman-Carroll法对C_(6)H_(12)O_(6)-SiO_(2)-Mg体系的DSC曲线进行拟合分析,得出镁热自蔓延反应的活化能E=−103168 kJ/mol,反应级数n=0.3786。The work aims to study the evolution of phases and the reaction mechanism of organic carbon sources in the process of preparing SiC powder by the magnesiothermic self-propagation method.The impact of Mg powder and glucose addition on SiC powder preparation was investigated through the magnesiothermic self-propagation method with SiO_(2),Mg powder and glucose as the raw materials.Thermodynamic analyses demonstrated that in the C_(6)H_(12)O_(6)-SiO_(2)-Mg system,the Gibbs free energy of the SiC-generating reaction exhibited an increase with rising temperature,while the impurity content within the system demonstrated a corresponding rise.This was identified as an impediment to the effective synthesis of SiC.The experimental data indicated that the addition of Mg powder resulted in a gradual enhancement of the diffraction peak intensity of the Mg_(2)Si phase in the reaction product,accompanied by a simultaneous weakening of the diffraction peak intensity of the SiO_(2)phase.Conversely,the addition of glucose led to a weakening of the diffraction peak intensity of the Mg_(2)Si phase,accompanied by a tendency for the yield of the SiC product to initially increase and subsequently decrease.Following an acid washing treatment with an HF solution,the product was found to be single-phase SiC.In conclusion,the optimum yield of SiC is determined to be 51.9%under the aforementioned conditions of a 30%excess of glucose and an 80%excess of magnesium powder.The activation energy of the magnesium thermal self-propagation reaction,E=−103168 kJ/mol,and the number of reaction stages,n=0.3786,are obtained by applying the Freeman-Carroll method for the DSC curve fitting analysis of the C_(6)H_(12)O_(6)-SiO_(2)-Mg system.

关 键 词：SIC 镁热还原法 SiO_(2) 碳源 葡萄糖 

分 类 号：O621.251[理学—有机化学]