High Quality Spinel Powders for Missile Dome Applications

Period of Performance: 01/16/2003 - 07/15/2003


Phase 1 SBIR

Recipient Firm

TDA Research, Inc.
12345 W. 52nd Ave. Array
Wheat Ridge, CO 80033
Principal Investigator


Smart weapons are increasingly being used to improve targeting efficiency, minimize collateral damage and avoid civilian causalities. Whereas only about 10 percent of the bombs used in Operation Desert Storm were so-called "smart weapons," so far in Afghanistan about 90 percent have been precision-guided weapons. For optical target recognition and guidance, infrared, visible and laser frequencies are being used. This requires the use of transparent missile domes. The domes must transmit infrared and visible light with high resolution and low signal loss while exposed to extreme conditions. Sapphire is one of the few materials that meets both the mechanical and optical operational constraints. Unfortunately due to the excessive diamond grinding that is needed to produce a dome shape, sapphire domes are very expensive. Spinel has been qualified for domes in several missile systems and can be hot-pressed to near net shape, greatly reducing the grinding needed and thereby greatly reducing cost. Unfortunately, impurities in the starting materials adversely affect the yields and quality of the transparent spinel domes. Using TDA's patented metal-exchange process, we will produce high quality spinel powders from boehmite sols. The precursor materials are expected to yield higher quality spinel domes with better final product yields. A high quality spinel powder with good densification characteristics will provide a lower-cost route for fabrication of transparent spinel domes. The availability of spinel domes will allow the Department of Defense to use spinel domes in place of the more expensive sapphire domes. The availability of lower-cost high quality transparent spinel will also allow fabrication of transparent armor and allow commercial users to replace sapphire with spinel in industrial applications.