The proposed Phase 1 program will demonstrate the feasibility of large ceramic to metal joints/seals that can tolerate extreme environments. The immediate application of the work is bonded sapphire viewports for a Venus probe. TvU's commercial viewport products have demonstrated that the pressure and temperature constraints of the surface of Venus will be met, while the use of materials appropriate to the atmospheric conditions will satisfy the overall physical constraints. The ceramic bonding and viewport systems will be shown to be adaptable to overall NASA use constraints. Task work will detail the design of the ceramic to metal joining process as well as a generic viewport design. A variety of alumina and sapphire fixtures will be fabricated and tested under wide thermal and mechanical conditions. A specific prototype viewport will be designed, fabricated and tested at Venus lander atmospheric conditions in Phase 1. Phase 1 work will lay out the foundation for a variety of prototype systems developed and tested in the Phase 2 program. Anticipated
Benefits: NASA applications include vehicle and probe viewports, plus research facility applications. Vehicle applications include viewports that allow camera access to monitor vehicle status and operating condition, vehicle surface condition and temperature, and the vehicle's external environment. Probe viewports allow the probe to interact optically with the probe's environment. Important non-technical applications of viewports include sales efforts, employee morale, and accident investigations. Commercial applications are focused on harsh environment imaging and large ceramic to metal seals. Application to the Imaging/Viewing market focuses on providing the means to effectively visually monitor inside the boundaries of thermal, chemical, vacuum and pressure systems. Vision is a global, but critically important monitoring process useful for general and specific understanding of visible processes. Optical processing is typically focused on a specific optically detectable parameter, such as temperature, spectroscopic information, or active optical probing, and is used for more direct process control, and especially for automated processes. A simple method for joining/sealing large ceramics to metal has broad application in hot filtering, and hot ceramic structures.
