论文部分内容阅读
以硼酸钠、镁和碳为原料,采用燃烧合成技术制备碳化硼粉体,并研究了初始条件对燃烧产物的组成和显微结构的影响。结果表明:反应物中过量的镁粉和合适的坯体相对密度下获得的燃烧产物杂质含量较少;通过酸洗和水洗得到了不含杂质的碳化硼粉体。燃烧合成碳化硼的反应机理研究表明,硼酸钠首先分解为氧化硼,然后发生镁还原氧化硼及其碳化反应,最终生成碳化硼。
The boron carbide powders were prepared by combustion synthesis using sodium borate, magnesium and carbon as raw materials. The effects of initial conditions on the composition and microstructure of the products were studied. The results show that the relative content of excess magnesium in the reactants and the relative density of the green body is less than that of the combustion products. The boron carbide powder without impurities is obtained by pickling and washing. The reaction mechanism of the combustion of synthetic boron carbide shows that sodium borate is firstly decomposed into boron oxide, and then magnesium reduced boron oxide and its carbonization reaction occur to finally produce boron carbide.