采用化学气相沉积法制备了块体非晶态Si-C-N陶瓷.用TG/DSC、XRD,SEM和TEM等技术方法研究了所制备的Si-C-N陶瓷的热行为.研究结果表明:在热处理过程中,非晶态Si-C-N首先发生相分离,分离后的一种相呈颗粒状;β-Sic就是从这种颗粒状的分离相中形成.在热处理条件下,非晶Si-C-N的晶化温度约为1200℃;在加热速率为20℃/min的连续加热条件下,其晶化温度为1372.6℃.β-sic在1200℃首先形成,β-Si3N4和α-sic则在1500℃形成.在扫描电镜观察中,热处理后的Si-C-N中出现一种类似于层状的组织,这种组织的晶化程度较高.%The amorphous bulk Si-C-N ceramic was prepared by chemical vapor deposition (CVD). The thermal behaviors of as-prepared Si-C-N ceramic were investigated using TG/DSC, XRD, SEM and TEM. The phase separation firstly occurred in amorphous Si-C-N during the heat treatment, and one of separating phases appeared granular. 尾-SiC was formed in the granular separating phase. The amorphous Si-C-N began to crystallize at about 1200鈩?when the ceramic exposed to the heat treatment. The crystallization temperature was about 1372.6鈩? which was determined by DSC under the condition of continuous heating at a heating rate of 20鈩?min. 尾-SiC was found at 1200鈩? while 尾-Si3N4 and 伪-SiC were formed at about 1500鈩? A laminate-like structure appears in the heat-treated Si-C-N. This kind of structure was proved to be the highly crystallized Si-C-N.
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