SiC预制件的制备

Preparation of SiC Preforms

采用淀粉、硬脂酸和石墨三种造孔剂及粘结剂,用连接法和氧化连接法制备SiC预制件。采用TG-DTA/DSC,SEM,EDS和XRD等测试方法研究了淀粉、硬脂酸、石墨和SiC颗粒的氧化特性及烧结后预制件的微观结构及材料的物相构成。研究结果表明:在空气气氛中,造孔剂淀粉、硬脂酸和石墨在不同的温度下氧化殆尽,SiC颗粒发生了氧化现象,SiC颗粒表面生成了SiO2层。

With three different pore-forming agents of starch,stearic acid and graphite,and binder bonding,SiC preforms were fabricated with the method of the combination of the sintered shaping of SiC preform and pressureless infiltrating.By test methods of TG-DTA/DSC、SEM、EDS and XRD and so on,oxidation characteristic of starch,stearic acid,graphite,SiCp,and micro-structure and phase structure of performs have been studied.The results show that pore-forming agents of starch,stearic acid and graphite oxidize to end at different temperature,and SiCp produces oxidation in air,and SiCp surface produces SiO2.