Sapphire Statistical Characterization and Risk Reduction Program

Published

September 1, 2001

Author(s)

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

Abstract

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

Volume

4375

Conference Dates

April 16-20, 2001

Conference Location

Adelaide, 1, AS

Conference Title

SPIE Meeting

Pub Type

Conferences

Keywords

fracture, nondestructive evaluation, sapphire, strength

Citation

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 October 6, 2024)