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	Experimental investigation on electrical discharge diamond grinding of RB-SiC ceramics 期刊论文 OAI收割 International Journal of Advanced Manufacturing Technology, 2018, 卷号: 94, 期号: 2019-05-08, 页码: 2751-2762 作者: Rao, X. S.; Zhang, F. H.; Li, C.; Li, Y. J. \| 收藏 \| 浏览/下载：49/0 \| 提交时间：2019/09/17 Electrical discharge diamond grinding RB-SiC ceramics Surface quality Material migration bonded silicon-carbide material removal rate surface-roughness spark assistance micro-edm breakdown optimization prediction electrodes composite Automation & Control Systems Engineering
	Technology on fabrication of precise SiC aspherical mirror (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Materials and Products Manufacturing Technology, ICMPMT 2011, October 28, 2011 - October 30, 2011, Chengdu, China Zhang Z. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 This paper represents a technique to produce the large size optical aspherical mirror by using reaction-bonded silicon carbide to meet the material requirements of the space used mirrors based on the characters comparison of all types mirror material. Techniques are described in this paper including the bonding procedure of silicon carbide to form a mirror shape the CCOM technology for aspheric grinding polishing on a home-developed tool -FSGJ-2 and the aspheric profilometry. A specialized Offner Null lens is also developed to measure the aspherical mirror with laser interferometer. With the technology depicted in the paper a 502mm 298 mm off-axis SiC aspherical mirror is successfully made with a surface accuracy better than 1/50rms the final result meets the design requirement. (2011) Trans Tech Publications.
	Manufacture of 1.2m reaction bonded silicon carbide mirror blank CFID (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang G.; Zhang G.; Zhang G. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 Silicon carbide (SiC) is a new type candidate material for large-scale lightweight space mirror. Its low thermal distortion high stiffness fine optical quality and dimensional stability make SiC an ideal material for large space born telescope. Since ten years Changchun institute optics fine mechanics and physics (CIOMP) has developed reaction bonded SiC (RB-SiC) technology for space application and can fabricate RB-SiC mirror with scale less than 1.0 meter for telescope. The green body is prepared with gel-casting method which is an attractive new ceramic forming process for making high-quality complex-shaped ceramic parts. And then unmolding drying binder burning out reacting bonded the RB-SiC can be obtained. But with the development of space-born or ground telescope the scale of primary mirror has exceeded 1.0 meter. So CIOMP has developed an assembly technique which called novel reaction-formed joint technology for larger RB-SiC mirror blank. The steps include joining of green bodies with mixture comprised of SiC particles and phenolic resin etc firing machining and sintering. Joining the 1.2 meter RB-SiC mirror blank by the novel reaction-formed joint technology. And testing the welding layer's performance the results show that the thickness of 54-77m the microstructure and thermal property can be comparable to the substrate and the mechanical property are excellent in bending strength of 307MPa. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Fabrication technique of large-scale lightweight SiC space mirror (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhang G.; Zhang G.; Zhang G. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 Silicon carbide (SiC) is a new type candidate material for large-scale lightweight space mirror. Its low thermal distortion high stiffness high optical quality and its dimensional stability are better than other traditional optical substrate materials such as ULE Zerodure Beryllium (Be) and so on. In this paper the lightweight silicon carbide space mirror blank was fabricated by reaction sintering. As a space born mirror material silicon carbide must be an optical grade ceramic. So we prepared the silicon carbide green body with gel-casting method. Then some carbon materials were supplemented into the green body which will bring reaction-sintering with silicon in a vacuum furnace during 1500-1600C ultimately the reaction bonded silicon carbide was made. The diameter of SiC space mirror blank we have made is 680mm. If expanding the size of the vacuum furnace bigger mirror blank can be obtained. The test results show that the mechanical and thermal properties of RB-SiC are excellent with bending strength of 350MPa fracture toughness of 4.1 MPa·m1/2 and coefficient of thermal expansion(CET) of 2.6710-6/K. The surface roughness(RMS) could be better than 3nm.