Effect of Propellant Combustion on Sapphire

  • Mark L. Bundy US Army Research Laboratory, Aberdeen Proving Ground
Keywords: Laser beam transmission, Laser ignited guns, Breech face, Substrate material, Sold thin film thermocouple


Sapphire (Al2O3) is the window material of choice for laser beam transmission into the combustion chamber of laser-ignited guns. To evaluate the long-term effects of propellant combustion on an Al/sub 2/O/sub 3/ laser window, it is important to know the window temperature during firing. This paper presents temperature data on an Al/sub 2/O/sub 3/ sample located in the breech face of the gun where the laser window would be in a laser-ignited 155 mm(M199) cannon. Al/sub 2/O/sub 3/ sample is a substrate material of a commercially sold thin-film thermocouple, and is therefore thermally, if not optically, representative of an actual Al/sub 2/O/sub 3/ laser window.

Author Biography

Mark L. Bundy, US Army Research Laboratory, Aberdeen Proving Ground
Dr Mark L BuDdy is research physicist. He has been working at the US Army Research Laboratory,MD, since 1981. His area of expertise is gun accuracy.


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How to Cite
Bundy, M. (2013). Effect of Propellant Combustion on Sapphire. Defence Science Journal, 50(4), 393-400. https://doi.org/10.14429/dsj.50.3750
Chemical Science & Technology