Patent ID: 7026011

Claim:
A method for applying an aluminide coating on a gas turbine engine blade having an external surface and an internal cooling cavity defined by an internal surface that is connected to the external surface by cooling holes, the method being conducted in a vapor coating container having a hollow interior coating chamber, the method comprising the steps of: (a) loading the coating chamber with the blade to be coated; (b) providing an aluminide coating gas in the loaded coating chamber; (c) maintaining the loaded coating chamber comprising the aluminide coating gas at a temperature of from about 1000 to about 1125° C. for from about 0.5 to about 4 hours with no inert or nonoxidizing carrier gas introduced into the chamber, or if an inert or nonoxidizing carrier gas is introduced into the chamber, the gas flow rate is less than about 20 ft 3 /hour, to deposit an aluminide coating on the external surface of the blade; and then (d) flowing an inert or nonoxidizing carrier gas into the loaded coating chamber comprising the aluminide coating gas at a gas flow rate of from about 20 to about 150 ft. 3 /hour (about 566 to about 4248 liters/hour) for from about 0.5 to about 4 hours to move the aluminide coating gas through the cooling holes and internal cooling cavity of the blade, while maintaining the loaded coating chamber at a temperature of from about 1000 to about 1125° C., to deposit an aluminide coating on the internal surface of the blade.