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This paper presents experimental results regarding a new approach to smart radiator devices (SRD) employing a smart, integrated thin-film structure based on V1-x-yMxNyOn that can be applied to existing thermal blankets such as Kapton or to thermal radiators such as Al. The smart coating facilitates thermal control by dynamically modifying the thermo-optic characteristics of the underlying substrate in response to the ambient temperature and/or a control voltage. This methodology has significant advantages over competitive technologies in terms of weight, cost, structural simplicity, and integration with the space structure. The effective emissivity of the film/substrate structure can be reduced dynamically by changing the behavior of the smart coating from insulator to metallic. High quality VO2 films have been prepared using a hybrid reactive laser ablation technique.

MPB has developed advanced smart radiator devices (SRDs) for passive, dynamic thermal control of space structures and payloads. The SRDs employ a nano-engineered, integrated thin-film structure based on V1-x-yMxNyOn. Dopants, M and N, tailor the transition temperature characteristics of the tuneable IR emittance. This paper describes the progress in MPB's smart thermal radiator towards its validation as an efficient thermal control device for space environment. A set of environmental tests were performed in order to validate the coating resistance and performance stability in space. The tests included random vibration, thermal shock, and accelerated aging. In addition, the thermo-optic characteristics after exposure to Atomic Oxygen (AO) in a simulated LEO environment were similar to the “as deposited” characteristics. Preliminary radiation tests, comparable to 3 years in a GEO environment, indicate very low change in emissivity and solar absorptance relative to the initial values.