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Sapphire Statistical Characterization and Risk Reduction Program



Donald McClure, Robert Cayse, David R. Black, Steven Goodrich, K Lagerloef, D Peter, Daniel C. Harris, Dale McCullum, Daniel H. Platus, Charles E. Patty, Robert S. Polvani


The Sapphire Statistical Characterization and Risk Reduction Program tested 1400 4-point flexure bars with different crystal orientations at different temperatures to establish a mechanical strength database for engineering design. Sapphire coupons were selected to represent surfaces on two different missile windows and a missile dome. Sapphire was obtained from the same suppliers used for the windows or dome and, as much as possible, coupons were fabricated in the same manner as the corresponding part of the window or dome. For one missile window, sapphire from one fabricator was 50% stronger than sapphire made to the same specifications from the same blanks by another fabricator. In laser thermal shock tests, sapphire performed better than predicted from flexure tests. Of several nondestructive methods evaluated for their ability to identify mechanically weak specimens, only x-ray topography was correlated with strength for a limited set of specimens.
Conference Dates
April 16-17, 2001
Conference Location
Orlando, FL
Conference Title
Intl Society for Optical Engrg (SPIE)


mechanical strength, nondestructive evaluation, sapphire


McClure, D. , Cayse, R. , Black, D. , Goodrich, S. , Lagerloef, K. , Peter, D. , Harris, D. , McCullum, D. , Platus, D. , Patty, C. and Polvani, R. (2001), Sapphire Statistical Characterization and Risk Reduction Program, Intl Society for Optical Engrg (SPIE), Orlando, FL (Accessed June 25, 2024)


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Created January 1, 2001, Updated February 19, 2017