Method of deposition of metallic coatings using atomized spray

摘要

A method of coating a metal substrate such as the components in second and third stages of gas turbine engines in order to increase the oxidation and corrosion resistance of the metal substrate under high temperature operating conditions, the method including the steps of forming a powdered mixture of a high-melt superalloy or MCrAlY component, where M comprises Fe, Ni and/or Co, and a low-melt component containing about 2-5 wt. % silicon, boron or hafnium, applying the powdered mixture to the surface of the metal substrate at room temperature using an atomized spray to form a uniform surface coating, and then heating the coated substrate surface under vacuum conditions to a temperature in the range of about 1900° F. to 2275° F. to obtain a uniform coating composition providing oxidation resistance to the underlying substrate.

主权项

1. A method of coating a metal substrate on a gas turbine engine in order to increase the oxidation resistance of said substrate at high temperature, comprising the steps of:
forming a powdered mixture of a high-melt superalloy component or MCrAlY, where M comprises Fe, Ni and/or Co, a lower-melting component containing a melting point depressant, said melting point depressant comprising silicon, boron, hafnium or gold, and a binder material for said powdered mixture; applying said powdered mixture to a surface of said metal substrate at room temperature using an atomized spray to form a coating of substantially uniform thickness on said substrate surface; and heating said coated substrate surface under vacuum conditions to a temperature in the range of about 1900° F. to 2275° F., said temperature and vacuum conditions being sufficient to liquefy said lower-melting component and remove said binder material and form a liquid phase in which the higher melting powders become suspended in said liquid phase and develop a metallurgical bond to said substrate by liquid phase sintering.