Patent ID: 7294361
Filing Date: 2007-11-13
Classification: C23C

Abstract:
1. A process for gas-phase diffusion coating of a metallic component, comprising the steps of: defining a concentration of a metal halide as a coating gas at a surface of the metallic component that, for a defined coating time period, results in a defined diffusion coating layer; coating the surface of the metallic component with a first concentration of the metal halide for a first time period in a first coating process, wherein the first concentration is greater than the defined concentration; and coating the surface of the metallic component with a second concentration of the metal halide for a second time period in a second coating process, wherein the second concentration is lower than the defined concentration and greater than zero; wherein a sum of the first time period for the first coating process and the second time period for the second coating process is less than the defined coating time period, wherein a diffusion coating layer on the metallic component that results from the first coating process and the second coating process equals the defined diffusion coating layer, and wherein the first coating process and the second coating process are conducted in succession without an intermediate purging process step.