Abstract: Near-net-shape replication and ion beam figuring technologies were investigated for chemical vapor deposited (CVD) SiC to fabricate high performance, glancing incidence Wolter Type I x-ray mirrors. Small scale CVD experiments were performed on graphite mandrels to demonstrate replication of SiC shells that closely matched the design of the XMM 40th shell at 1/16th scale. The SiC shells were successfully separated from the graphite mandrels and then machined to the required dimensions. Ion beam figuring as a final fabrication step was investigated on Wolter Type I replicated SiC surfaces. Angular sputtering yields and surface roughness evolution with material removal were found to be sufficiently well behaved to favor ion beam figuring as a means of performing the final figuring step. The CVD-SiC fabrication technology for the x-ray telescopes as developed above appears scaleable. Finally, analysis of a single element CVD-SiC telescope, modeled after the AXAF-S 26th shell showed telescope deflections and weight to be 2.23 and 2.77 times less, respectively, than for a nickel replicated shell of the same dimensions. !23
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