No abstract

This paper describes POCO's new capability to rapidly produce large silicon carbide mirror substrates by conversion joining segments of silicon carbide during the process of converting graphite to silicon carbide. Mirror segments and structures are machined from a special graphite and subsequently joined together during the conversion process with the end result being a high purity beta silicon carbide structure. Interface boundaries are removed by the crystal growth across boundaries as the graphite crystal structure is converted to the larger crystal size of silicon carbide. Results of conversion joining development, design guidelines and limitations of the conversion joining process will be presented. INTRODUCTION: