Adaptive Thermal Control Material Systems and Coatings for Radiation Hardening of Spacecraft

ABSTRACT: The purpose of this SBIR phase II proposal is to validate design and material and process engineering that demonstrated feasibility of processing the adaptive thermal control material system (TCMS) that is capable of providing a radiation hardened space stable performance along with the needs of the charge storage capability. Through this proposal the several engineered TCMS concepts for the space craft protection are planned for the validation for the needed survivability and better protection of the space assets and the involved investments. Each of them can mature to various degree of readiness level per the planned efforts. The over all goals here is to develop and validate concepts for an adaptive TCMS that can protect spacecraft structures and payload electronics from high flux radiation doses from the natural solar storm induced events and possible manmade nuclear threats in a given orbit. The new TCMS designs as well as the processing approaches can provide the usual TCMS functions in reliable and space stable manner, plus a charge storage coating to meet the desired goal, where one can adapt to accommodate high dose of electron flux by storing and dissipating the charges per the designed time constants chosen for the material design. Under this new suggested approaches for the validation, the adaptive TCMS and ESD capable thermal control material system is allowed to accumulate as much charge as possible through a designed storage mechanism with the goal of maintaining surface voltage to acceptable small values, and with possible elimination of the dielectric breakdowns, and the electrical discharges. To fulfill this goal of the solicitation, various efforts for the validation of the TCMS designs are suggested to provide good passive thermal control performance by providing: low space stable Solar Absorbtance, & high thermal emittance, good adhesion to various technologically important substrates and thermal cycling resistance for the needed operational temperature limits set by the mission orbital needs, along with the needed good electrical properties to assure low acceptable surface charging using currently available space stable material systems. The concepts that are adaptable to the current second surface mirror technology in conjunction with the suggested transparent space stable multilayer ceramic capacitor stack for the charge storage are also being considered for the validation. Finally, the suggested material design are expected to be validated to meet reliability needs of the space environment for a typical ten year mission lifetime and conform to the mission space qualification requirements including high vacuum, microgravity, radiation, atomic oxygen, low out gassing, and high launch loads. We anticipate the validation to be successful based on phase I results and also because most of the suggested material components are chosen from the materials that have been either already qualified as space materials or have some heritage of been flown on some missions for other intent. BENEFIT: Military Application: Many DOD space and avionics systems, including communications and navigation satellites, could benefit from increased protection from the effects of space weather. Commercial Application: Space, avionics and terrestrial commercial systems, including satellites, aircraft avionics and automobiles, could benefit from sever space weather protection systems. Success in charge storage concept may open various market sectors due to the appeal of device technology for light weight and ultra high charge storage density along with the involved very small charging & discharging times.