High Thermal Shock Resistance AIN For Infrared Window Applications

A very attractive alternative for an IR sensor is an uncooled IR window, which can operate in the highly aerothermal environment of a surface-to-air missile. This program proposes to develop an uncooled IR window for IR sensors, which can operate in the aerothermal environment of a surface-to-air missile. The mild thermal shock parameter, R?, of aluminum nitride (AlN) is approximately one order of magnitude higher than the other infrared materials. The innovative idea in this program is to use unique powders and a special sintering aid to achieve a nanosized grain microstructure so that true transparency can be achieved. The transparent AlN developed in this program can be used to replace translucent Al2O3 for sodium and halogen lamp applications. It can also be used for IR missile domes, transparent armors, undersea submersibles, supermarket scanners, glass for Xerox copy machines and scanners, and optical lenses. This new material can have significant impact on the optical industry by replacing specialty glass and sapphire.