METHOD FOR FORMING FILM BY USING ACTIVATED FOAM TECHNIQUE

摘要

PURPOSE: A method for forming film by using activated foam technique is provided to coat substrates that are exposed to high temperatures such as turbine engine components. CONSTITUTION: The method for coating internal passageways of an airfoil of a turbine engine includes (i) providing an airfoil having internal passageways, the airfoil comprising a nickel-base or cobalt-base superalloy; (ii) coating the internal passageways with a foam suspension containing an aluminum powder suspended in a foam; (iii) heat treating the foam suspension at a temperature to volatilize the foam to form an aluminum-base coating along the internal passageways; and (iv) subjecting the substrate to a diffusion treatment to diffuse aluminum into the substrate, wherein the coating includes an activator containing a halide element that complexes with the aluminum of the aluminum base coating.