Magnetic Fabrication of a Whisker-Toughened Ceramic Thermal Gradient Gun Barrel

This project develops an innovative and efficient ceramic/metal thermal gradient gun barrel which provides a linear gradient in material and density from a fully ceramic interior to a fully metallic exterior. We will develop a barrel insert and magneticslip casting process to fabricate a material that gradually changes from pure ceramic at the bore, through a mixed ceramic-metal matrix, to a pure metal. This ensures a strong bond between the ceramic and metal while spreading the thermal/ mechanicalstresses through the gradient area. The metal outer layer interfaces with a conventional metal or composite barrel. Slip casting of a fine steel whisker-toughened ceramic subjected to centrifugal rotation and magnetic fields produces a linear distributionof the ceramic matrix from a pure ceramic to a sintered metal. The ceramic/metal gradient material can be used for five inch, eight inch or155 millimeter liners. This new barrel reduces life cycle costs by extending barrel life, eliminating spares anddecreasing inventories. Theoretical development, solid/fluid modeling and experiments will demonstrate the feasibility of our concept. This new material design technology can be manufactured at costs comparable to materials currently being used and can beretrofitted to existing weapons. Ceramic/metal thermal gradient barrel technology has direct applications for the military and commercial arms industry. Other applications include: (1) Military fire (mortar) barrels, (2) Military large armaments andartillery, (3) High pressure military and commercial fluid flow applications, (4) Wear-resistant surface under high temperatures and pressures, (5) Protective surfaces for military armor and lightweight military and law enforcement body armor. In addition,this technology has significant potential use for industries requiring a wear-resistant surface under high temperatures and pressures such as: diesel engines, brake rotors, flywheels, clutch plates, stoves and boilers.