DEVELOPMENT OF A TECHNOLOGY FOR THE SURFACE STRENGTHENING OF BARREL CHANNELS IN THE LARGE-CALIBER ARTILLERY GUNS

High temperatures and exposure to the chemical effect of powder gases that accompany artillery salvos actively destroy the surface layer of a barrel channel material. This disrupts the geometry of a barrel channel, thereby reducing the accuracy of an artillery gun aimed firing. We have proposed a technology of surface plastic deformation of the channel inner surface for strengthening the barrels of large caliber artillery and tank guns. The strengthening implies the cold-work hardening of a barrel channel metal with spherical deforming bodies that are mounted onto a massive cylindrical reinforcer. During machining, the reinforcer is driven into a rolling motion over the treated inner surface of a barrel channel and moves along the geometrical center of the machined gun’s barrel. As a result of such a hardening treatment, the residual compression stresses form in the thickness of a barrel channel material, thereby improving its surface microhardness. That contributes to an increase in the resistance of a barrel channel material against its burn-out and wear during artillery salvos. The reinforcing equipment for the implementation of such a treatment includes a reinforcer in the form of a cylinder with deforming bodies, an electric motor of the drive, and a mechanism to transfer the torque from the motor shaft to the reinforcer. During strengthening treatment, the set-up moves along a gun barrel channel, cold-working its material. The ensured hardening thickness is 0.15‒0.20 mm. The hardened surface layer of a gun barrel material, due to the heightened microhardness, firmly opposes the formation of operational microcracks within it. The compression stresses, formed in the thickness of a barrel channel metal, resist the temperature propagation of microcracks. Owing to this, the resistance of the hardened barrel metal against operational destruction increases, thereby improving the reliability and durability of costly artillery armament