Nicalon SiC纤维增强SiC复合材料制备工艺研究

Study on Preparation and Characterization of SiC Composites Reinforced with Nicanlon SiC Fibers

本文对SiC纤维增强SiC复合材料的制备工艺进行了研究。将NicalonSiC短纤维、SiC颗粒、钾长石、高岭土按设计的配方通过干法混合,干压成型后采用常压烧结法制备出SiCf/SiC复合材料;利用DTA分析混合粉体的热物理性能,采用XRD分析烧成前后材料的物相,利用SEM观察样品的显微结构,并测定了样品的致密度和抗弯强度。研究结果表明:常压烧结温度1115℃,保温时间2h可制备出性能良好的SiC/SiC复合材料。

The preparation of SiC-fiber-reinforced SiC composite was studied in this study. Nicanlon SiC fiber, SiC particle, potassium feldspar and kaolin clay with designed ratios were mixed by a dry bailing process. The obtained powders were suppressed and then sintered at 1100 - 1145℃. The techniques of DTA, XRD and SEM were used to analyze the phases, thermostability and microstructures of the starting materials and the SiCf/SiC compacts sintered. Densities and bending strengths of the SiCk/SiC compacts were also measured. The results showed that the SiCf/SiC compact prepared at 1115 ℃ with a heat preservation of 2 h was of optimum properties.