C/C复合材料与LAS陶瓷连接的显微结构与性能
Microstructure and Properties of Joints of Carbon/Carbon Composites and LAS Glass-Ceramic
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摘要: 采用Y2O3-Al2O3-SiO2-TiO2(YAST)玻璃作为中间层,对SiC-MoSi2表面改性的C/C复合材料与Li2CO3-Al2O3-SiO2(LAS)陶瓷进行热压连接,所施压力为20MPa,保温时间为30min,连接温度分别为1150℃,1200℃,1250℃,1300℃。利用SEM,EDS和BEI(背散射电子像)对SiC-MoSi2涂层,连接界面的形貌和断口进行了分析,研究结果表明,SiC-MoSi2涂层与基体结合紧密,Si、C元素在界面处呈梯度状分布,形成厚度约为15μm的过渡层。YAST玻璃与基体润湿良好,接头的剪切强度可达26.21MPa。Abstract: Carbon-carbon(C/C) composites modified with the SiC-MoSi2 coating were joined to Li2CO3-Al2O3-SiO2(LAS) ceramic with Y2O3-Al2O3-SiO2-TiO2(YAST) glass as intermediate layer under joining pressure of 20MPa and holding 30min at various temperature.The effect of joining temperature,holding time and joining pressure on the share strength was studied.The microstructure of the interface were analyzed by SEM,BEI and EDS.Result shows that Si and C elements were gradient distributed in the interface and a interlayer about 15μm formed which helps the adherence of SiC-MoSi2 coating to C/C composite.The YAST glass has favorable wettability with C/C composites and LAS ceramic and maximum shear strength of joints reaches 26.21MPa.