A Light Weight Titanium Alloy Machine Gun Barrel with a Ceramic Liner

Current rapid fire guns used by the Marines overheat during sustained rapid firing. As a result they are subject to failure in combat situations placing the war fighter at risk. The use of a gun barrel with greater refractory capability than the current steel barrels would present a true solution to this problem. A ceramic lined gun barrel would have excellent resistance to failure from excessive heat and erosion. In addition ceramics are of much lighter weight than steel. Silicon nitride (Si3N4)-based ceramics have demonstrated the potential to be used as gun barrel liners. MER has been working to develop the capability to produce Si3N4 gun barrels with rifling that is produced as part of the fabrication process. In this Phase I program, MER will demonstrate the fabrication of a Si3N4 gun barrel liner with a design selected by the Marines. A Ti-6Al-4V barrel will then be built up around this ceramic liner to provide a light weight rapid fire barrel with capabilities greatly exceeding those of the current all steel designs. The buildup of the Ti-6Al-4V on a ceramic liner has already been demonstrated by MER using a rapid additive manufacturing process.