碳对碳热还原氮化天然石英物相行为的影响

采用XRD、SEM等研究了碳添加量（理论量、碳过量5％、10％、20％、50％和100％），不同碳源（焦炭和炭黑）对反应产物的影响。结果表明，C的添加量为理论量，在温度为1600℃时产物为β-Si3N4；在C的添加量为理论量过量10％时，也可以得到含量较高的β-Si3N4，但产物中存在的β-SiC的量相对较多；随着C的添加量的增加，各试样反应产物中β-SiC含量也逐渐增加，当C的添加量过量100％时，产物主要为β-SiC。合成温度在其他温度下（1500、1520、1540、1560℃和1580℃℃）都有相似的规律。碳源种类对反应产物的物相组成的影响较小。

Influences of Carbon Contents on the Products of Carbothermal Reduction-nitriding of Natural Quartz

The influence of carbon content （stochiometric content, exceeding 5%, 10%, 20%, 50% and 100%） and carbon species （cock and carbon black） on the final products＇ phases were studied by XRD, SEM and EDS. The results show that Si3N4 powders can be synthesized by carbothermal reduction nitridation of natural quartz at 1 600 ℃. However, at high temperature, the content of SiC in the reaction products increased with the increasing of the content of carbon, while the content of Si3N4 reduced relatively. A similar results can be obtained at other temperatures （1 500, 1 520, 1 540, 1 560 and 1 580℃ ）. Carbon species has a small impact on the phase composition of reaction products.