The Development of Refractory Materials as Gun Barrel Liners

"State-of-the-art gun barrels limit the munition and propellant that can be utilized due to excessive erosion that limits the life and performance capabilities and adversely affects the operating cost and required force levels. In order to increase barrellife, as well as accommodating the use of higher energy and temperature propellants for firing advance projectiles, the refractorness of gun barrels must be substantially enhanced. This program proposes to investigate the use of refractory metal alloysand cermets applied by solid free form fabrication (SFFF) using a plasma transferred arc (PTA) energy source. A variety of refractory alloys and cermets will be produced and screen tested utilizing a vented bomb and heat checking. Forcing cones will beproduced in the most promising compositions and delivered to the Navy which after testing will provide a basis for Phase II optimization, additional forcing cone testing and fabricating barrels for live fire test. Gun barrels with refractory metal alloylings have application in all military branches in all caliber weapons as well as commercial applications requiring reduced thermomechanical erosion."