Fabricating of Ф4m CIOMP-SiC mirror blank

Successful fabricating of φ4m silicon carbide (SiC) mirror blank after 20 years of research in Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP). Preparing 12 monolithic SiC green bodies with a partially closed back by lost foam and gelcasting technology, joining 12 SiC monolithic green bodies by reaction-formed technology, and densifying SiC mirror blank by reaction sintering technology. The testing results show that the performances of CIOMP-SiC could meet requirements, and the root mean square (RMS) value of φ4m CIOMP-SiC surface shape is better than λ/30 (λ=632.8nm).