230 Fundamental Study on ELID Grinding of Lightweight Mirror for Astronomical Telescope : Fabrication of CVD-SiC mirror by machining center

Abstract

The fabrication of CVD-SiC large-size mirrors for astronomical telescope has proven to be very difficult and time-consuming by utilizing ordinary methods. In order to conduct high efficiency machining of such mirrors, grinding process using metallic bond diamond wheels with electrolytic in-process dressing (ELID) would be effective. In this study, a series of fundamental experiments, such as investigations on ELID grinding characteristics of CVD-SiC and SiC ceramics, have been performed. Simultaneously, a CVD-SiC plane mirror with length 300 mm, has been fabricated by this ELID grinding method.