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Sapphire Statistical Characterization and Risk Reduction Program



D R. McClure, R W. Cayse, David R. Black, S M. Goodrich, K Peter, D Lagerloef, D C. Harris, D McCullum, D H. Platus, C 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.
Proceedings Title
Proceedings of Window and Dome Technologies and Materials VII
Conference Dates
April 16-20, 2001
Conference Location
Adelaide, 1, AS
Conference Title
SPIE Meeting


fracture, nondestructive evaluation, sapphire, strength


McClure, D. , Cayse, R. , Black, D. , Goodrich, S. , Peter, K. , Lagerloef, D. , Harris, D. , McCullum, D. , Platus, D. , Patty, C. and Polvani, R. (2001), Sapphire Statistical Characterization and Risk Reduction Program, Proceedings of Window and Dome Technologies and Materials VII, Adelaide, 1, AS (Accessed June 23, 2024)


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Created August 31, 2001, Updated October 12, 2021