Patent ID: 7531220
Filing Date: 2009-05-12
Classification: C23C

Abstract:
1. A method for forming a thick quasi-single phase platinum nickel aluminide coating over a nickel-based superalloy substrate, the method comprising the steps of: forming a metal layer over a surface of the nickel-based superalloy substrate, the metal layer comprising platinum; growing a diffusion zone from the metal layer and the nickel-based superalloy substrate, the diffusion zone comprising a platinum nickel alloy; and subjecting the platinum nickel alloy to a first aluminization cycle by depositing aluminum over the platinum nickel alloy and performing a first heat treatment diffusion cycle thereon to form a single phase beta platinum nickel aluminide layer; and performing a second aluminization cycle by depositing aluminum over the single phase beta platinum nickel aluminide layer and performing a second heat treatment diffusion cycle thereon to transform the single phase beta platinum nickel aluminide layer into the thick quasi-single phase platinum nickel aluminide coating comprising a beta platinum nickel aluminide additive layer having a zone including PtAl