ALLVAR Alloys for Athermalizing SiC Telescopes with Reduced SWAP-C

The Ultimate Goal of these research efforts is to develop ALLVAR Alloy athermalizing strut components that enable size, weight, cost, lead time, and performance enhancements of SiC mirrored optical seekers that must withstand extreme exo-atmosphere, endo-atmosphere, and mechanical loading environments. ALLVAR Alloys offer a brand-new strong and ductile support structure solution that can offer lower cost and lead time compared to legacy seeker telescopes, when combined SiC mirrors. The Phase I project modified the thermal expansion coefficient of ALLVAR’s commercially available Alloy 30 to reach the shortened lead time goal. This proposed Phase II project will buy down the risk associated with implementing this new alloy into seeker applications by collecting necessary material property data and beginning an incremental and iterative design, analysis, build, and test plan that includes thermal, shock, vibration, radiation, and optic performance testing. ALLVAR’s collaboration with Raytheon and Quartus Engineering, subcontractors on the project, identified 1) the acquisition of micro-creep, micro- yield, and basic material properties and 2) the design, building, and testing of an ALLVAR Alloy athermalized SiC primary mirror assembly under random vibration as the most important and highest risk elements to address in an incremental test plan. This Phase II project aims to address these highest risk next steps with the following Key Objectives: 1) Close quality and material property knowledge gaps for mirror holding, interfaces, and long-term stability of ALLVAR Alloys, 2) Design a multi-mirrored SiC telescope athermalized with ALLVAR Alloys, and 3) Fabricate and evaluate the performance of the telescope’s primary mirror mount in random vibration environmental conditions. This project includes thermal and vibration analysis of a multi-mirror system and vibration testing of a primary mirror assembly. If successful, this Phase II effort will provide a foundation for executing this test plan in future efforts with the aid and guidance of MDA and Raytheon. Approved for Public Release | 22-MDA-11340 (16 Dec 22)