摘要:
Energy, such as from one or more lasers, is directed at the surface of a substrate to mobilize and vaporize a constituent element (e.g., carbide) within the substrate (e.g., steel). The vaporized constituent element is reacted by the energy to alter its physical structure (e.g., from carbon to diamond) to that of a composite material which is diffused back into the substrate as a composite material. An additional secondary element, which can be the same as or different from the constituent element, may optionally be directed (e.g., sprayed) onto the substrate to augment, enhance and/or modify the formation of the composite material, as well as to supply sufficient or additional material for fabricating one or more coatings on the surface of the substrate. The process can be carried out in an ambient environment (e.g., without a vacuum), and without pre-heating or post-cooling of the substrate. Articles formed by the disclosed processes are described, including three-dimensional objects.
摘要:
The invention is a nonmetallic gun barrel having a longitudinally rigid tubular exterior capable of radial elastic deformation upon passage of a projectile therethrough. Liner segments fixed at the inner diameter of the barrel exterior are abutted end to end and form spiraled rifling structures comprised of shallow channels and ridges between the channels. Radial gaps between sides of the liners can be partly filled by radial projections of elastomeric material of the barrel exterior. The radial projections expand inwardly to seal against a projectile bearing against the inner periphery of the barrel as the projectile is fired from the barrel.
摘要:
The present invention provides a gun capable of operating at relatively higher temperatures. The barrel of the gun is made up of at least two layers. The inner layer is of a refractory material which may be a metal refractory or a non-metal refractory. The liner is bonded to an outer jacket material formed of an alloy of nickel, aluminum and molybdenum. The coefficient of expansion of the liner and of the jacket are relatively low so that the gun does not expand extensively when heated by intensive use. The jacket metal is of higher strength at elevated temperature than is the conventional gun barrel steel.
摘要:
Existence of cracks through the liner of a gun barrel is determined by sizing the outer tube of the barrel to expand and jam in the recoil jacket in response to pressure between the liner and the tube; or by providing electrical conductors between the tube and the liner which change their electrical characteristics when cracks form; or by permitting powder gases to leak through small openings in the tube as an indication of failure; or by a combination of these methods.