Patent ID: 6843861
Filing Date: 2005-01-18
Classification: C23C,F01D,Y02T,Y10T

Abstract:
1. A method for preparing a coated nickel-base superalloy article that is otherwise susceptible to the formation of a secondary reaction zone, the method comprising the steps of furnishing a nickel-base superalloy article substrate having thereon an initial aluminum-containing coating comprising an initial-coating additive zone and an initial-coating diffusion zone, the article being susceptible to the formation of the secondary reaction zone if heated to an elevated SRZ reaction temperature for an SRZ reaction period of time; thereafter removing the initial-coating additive zone and the initial-coating diffusion zone to expose a newly exposed surface of the article substrate that is substantially without cold work and residual stress; and thereafter depositing a subsequent aluminum-containing coating onto the newly exposed surface of the article substrate, the subsequent aluminum-containing coating including a subsequent-coating additive zone and a subsequent-coating diffusion zone, the article substrate with the subsequent aluminum-containing coating being otherwise susceptible to the formation of the secondary reaction zone if heated to the elevated SRZ reaction temperature for the SRZ reaction period of time.