Patent ID: 8333029
Filing Date: 2012-12-18
Classification: C23C

Abstract:
1. A process for manufacturing a gun barrel comprising the steps of: obtaining a bar of tool steel having a longitudinal axis, a front, a rear, and an exterior surface; hardening the bar of steel to a specified hardness; cutting the bar of steel to a specified length; drilling a hole through the bar of steel that is registered with the longitudinal axis of the bar of steel; reaming a bore through the bar of steel that is registered with the longitudinal axis of the bar of steel, thereby defining an interior surface of the bar of tool steel encompassing the bore; reaming a chamber in the rear of the bar of steel; preheating the bar of steel; heating the bar of steel to change the crystal structure of the bar of steel from ferrite to austenite; nitriding the bar of steel to create an oxide layer on both the exterior and interior surfaces of the bar of steel and a diffusion layer beneath each of the oxide layers; cooling the bar of steel; rinsing the bar of steel; and cleaning the bar of steel; and wherein a core of the bar of steel located between the diffusion layers has been hardened to a hardness of at least 50 HRC and not greater than 55 HRC.