Nano-Grain Partially-Stabilized Zirconia IR Windows

"MSI will develop nano-grain partially stabilized zirconia (PSZ) as an extremely durable MWIR window and dome material. PSZ has 3 times the fracture strength and 2 times the fracture toughness of sapphire, the most durable current IR window material, andits intrinsic IR absorption edge extends nearly 1 micron beyond that of spinel. PSZ is noncubic and therefore must be fabricated with a submicron grain size in order to reduce MWIR scattering to acceptable levels. During Phase I, fully dense PSZ sampleswill be fabricated using high purity nano-size powders and readily-scaleable densification methods that prevent significant grain growth. The fabricated samples will be optically, mechanically, and microstructurally characterized. This program willproduce fundamentally stronger MWIR windows and domes for use in extreme environments. Other applications include transparent armor and sensor windows for high temperature and erosive/abrasive environments."