粉末涂层法制备SiC_f/Ti先驱丝

POWDER COATED ROUTE FOR PRODUCTION OF SiC_f/Ti PRECURSOR FIBER

采用粉末涂层法制备了SiC_f/Ti复合材料先驱丝。胶粘剂为聚甲基丙烯酸甲酯(PMMA),溶剂为丙酮。用粘度计测定不同质量浓度溶液的粘度,确定了胶粘剂的临界浓度为0.03 g/mL,用化学分析方法测定胶粘剂在不同温度及不同压力下分解残余物的含量,研究了胶粘剂分解和逸出的动力学。胶粘剂的分解温度约为230℃,在350℃左右分解速率最大,低于400℃时分解完全。在分解温度范围内,同一压力下,随温度升高,分解速率和逸出速率增大;在同一温度下,随压力增加,胶粘剂的逸出速率减慢。确定了制备先驱丝的最佳工艺条件:烘干温度为110℃,电机走速电压为6.5 V,钛粉和胶的质量比为15:1。

In making Sic precursor fiber using a powder coated route, the binder, poly (methyl methacrylate) was used, and the solvent is acetone. The viscosity of the binder was tested by viscometer, and the critical concentration of the binder is 0.03 g/mL. The content of residual substance of the binder at different temperatures and pressures was test by chemical analysis. The volatility kinetics of the binder was also studied. The temperature for the binder decomposition is about 230 degreesC, the velocity reaches its maximum at about 350 degreesC, and the decomposition completed under 400 degreesC. The decomposition and transgression velocities increase when temperature is increased under the same pressure. The transgression velocity reduces when pressure is increased at the same temperature. The process of making uniform precursor was found by a uniformity design method.