C/C-SiC composites with SiC island distribution Were prepared via a new processing route. The fabrication process mainly included silicon infiltration by ultrasonic vibration, chemical vapor deposition (CVD), silico...C/C-SiC composites with SiC island distribution Were prepared via a new processing route. The fabrication process mainly included silicon infiltration by ultrasonic vibration, chemical vapor deposition (CVD), siliconizing, liquid phase impregnation and carbonization. The wear and friction properties were tested by an MM-1000 wet friction machine. The results show that SiC phases are mainly distributed between carbon fibers and pyrocarbons as well as among the pryoearbons. The dynamic friction coefficient of the composites decreases gradually from 0.126 to 0.088 with the increase of the surface pressure from 0.5 to 2.5 MPa at the same rotary speed. Furthermore, under the constant surface pressure, the dynamic friction coefficient increases from 0.114 to 0.126 with the increase of the rotary speed from 1 500 to 2 500 r/min. However, the coefficient decreases to 0.104 when the rotary speed exceeds 4 500 r/min. During the friction process, the friction coefficient of C/C-SiC composite is between 0.088 and 0.126, and the wear value is zero after 300 times brake testing.展开更多
空间系统用的高性能轻质反射镜的研究和应用正逐年稳定发展,本文从几种卫星反射镜材料的性能和特性出发,得出SiC及其复合材料作为反射镜材料性能最佳的结论;通过比较各种工艺制备SiC基反射镜性能,结果显示:只有C V D SiC能够作为反射镜...空间系统用的高性能轻质反射镜的研究和应用正逐年稳定发展,本文从几种卫星反射镜材料的性能和特性出发,得出SiC及其复合材料作为反射镜材料性能最佳的结论;通过比较各种工艺制备SiC基反射镜性能,结果显示:只有C V D SiC能够作为反射镜反射光学表面。本文重点详细介绍了SiC及其复合材料反射镜制备工艺及方法特点,并对其工艺发展前景进行了展望。展开更多
基金Project(2006CB600901) supported by the Major State Basic Research and Development Program of ChinaProject(0991015) supported by Guangxi Science Found, ChinaProject(200808MS083) supported by Guangxi Education Department Found
文摘C/C-SiC composites with SiC island distribution Were prepared via a new processing route. The fabrication process mainly included silicon infiltration by ultrasonic vibration, chemical vapor deposition (CVD), siliconizing, liquid phase impregnation and carbonization. The wear and friction properties were tested by an MM-1000 wet friction machine. The results show that SiC phases are mainly distributed between carbon fibers and pyrocarbons as well as among the pryoearbons. The dynamic friction coefficient of the composites decreases gradually from 0.126 to 0.088 with the increase of the surface pressure from 0.5 to 2.5 MPa at the same rotary speed. Furthermore, under the constant surface pressure, the dynamic friction coefficient increases from 0.114 to 0.126 with the increase of the rotary speed from 1 500 to 2 500 r/min. However, the coefficient decreases to 0.104 when the rotary speed exceeds 4 500 r/min. During the friction process, the friction coefficient of C/C-SiC composite is between 0.088 and 0.126, and the wear value is zero after 300 times brake testing.
文摘空间系统用的高性能轻质反射镜的研究和应用正逐年稳定发展,本文从几种卫星反射镜材料的性能和特性出发,得出SiC及其复合材料作为反射镜材料性能最佳的结论;通过比较各种工艺制备SiC基反射镜性能,结果显示:只有C V D SiC能够作为反射镜反射光学表面。本文重点详细介绍了SiC及其复合材料反射镜制备工艺及方法特点,并对其工艺发展前景进行了展望。
基金support for this study provided by the National HiTech Research Development Program of China(2006AA03Z560)Excellent Youth of Hunan Province,China(06JJ1007)~~