Ultra-Stable Zero-CTE HoneySiC and H2CMN Mirror Support Structures

NASA MSFC, GSFC and JPL are interested in Ultra-Stable Mirror Support Structures for Exoplanet Missions. Telescopes with Apertures of 4-meters or larger and using an internal coronagraph require a telescope wavefront stability that is on the order of 10 pico-meters RMS per 10 minutes. Interest is also for IR/FIR missions requiring 8-meter or larger diameter mirrors with cryogenic deformations <100 nm RMS. Fantom Materials is specifically responding to the need for ultra-stable mirror support structure traceable to the needs of Cosmic Origins for UVOIR, Exo and FIR telescopes, including mirror support structures, whiffle plates, delta frames and strongbacks. HoneySiC material has multiple features that make it very attractive as a potential future deployment hinge and latching material: 1) It's an additively manufactured Ceramic Matrix Composite (CMC) with no Coefficient of Moisture Expansion (CME). Individually molded parts become a monolithic construct, thus it is possible to manufacture an entire telescope using HoneySiC, 2) It's extremely light weight (HoneySiC panels have about 1/5 the density of beryllium, 3) It's extremely dimensionally stable due to a zero-CTE across a temperature range of -196C to RT. The thermal conductivity can be supercharged by addition of carbon nanotubes. The overarching program objective is to demonstrate HoneySiC as an ultra-stable structural telescope material. In Phase I, Fantom measured CTE and mechanical properties for HoneySiC HCMC and H2CMN to bring the basic material properties measurements closer to completion. In Phase II Fantom intends to is to continue collaboration with NASA MSFC, GSFC, JPL and Northrop Grumman Aerospace Systems in the design of a prototype whiffle plate, delta frame, tube structure or other optical structure that could be used to support mirror-class, space-based telescope applications, like the JWST Composite Backplane.