Spray Deposition of Aerogels as Thermal Barriers

Physical Sciences Inc. (PSI) proposes to develop and fabricate affordable, aerogel-based thermal protection systems (TPS) for use on a variety of hypersonic vehicles and projectiles. The Phase II program is focusing on developing, designing and fabricating TPS that will control heat "soak-back" within a railgun projectile. Heat flow to the instrument cavity will be minimized so that the cavity's temperature does not exceed 150°C. This TPS consists of a plasma sprayed graded structure containing aerogel particles for reducing thermal conductivity to 1000°C/second. As this technology transitions to use in the fleet during Options 1 and 2, the manufacturing cost of TPS will be cost competitive at $100/ part. The subcomponent and prototype testing will demonstrate the robustness of this design to withstand the thermomechanical stresses of launch and flight. BENEFITS: The unique TPS design proposed by PSI has three primary benefits: 1.) Manufacturing costs will be low as a result of using the inherently inexpensive spray deposition process that also controls the amount of aerogel consumed, eliminating waste. 2.) The graded insulating structure provides mechanical integrity that is not observed with current heat shield technologies. 3.) The 0.3 W/mK improved thermal conductivity provides a weight savings for missile applications. In addition to use on supersonic and hypersonic vehicles, the sprayed aerogel has applications on jet engine components, e.g., engine transoms, and industrial applications such as steam pipes.