The possibility for forming fused quartz layer on the substrate of carbon fiber reinforced fused quartz (CFRFQ) was investigated by melting fused quartz powder with an oxygen-hydrogen flame, chemical vapor deposition, and sol-gel method. Many kinds of bonding methods between fused quartz mirror surfaces and CFRFQ substrates were investigated, including hot- pressing directly with the mixture of fused quartz power and carbon fibers and hot-pressing secondly by adding powder between the mirror surface and the substrate. The fused quartz block could be bonded firmly under conditions of 20kg/cm2, 1240 degree(s)C, and 5 minutes, when silica powder prepared by sol-gel method was added in the midst. There is no crystallization in the middle silica layer, and the tensile strength is large. Three specimens with a diameter of 100mm and some small ones have been fabricated by this method, and the thermal deformation stability of this type of composite reflector is better than fused quartz mirror.
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