Patent ID: 6544346
Filing Date: 2003-04-08
Classification: B22D,B23P,C23C,C23G

Abstract:
A method comprising the steps of:providing an air-cooled component with a diffusion aluminide or MCrAlY bond coat on a surface thereof and a thermal-insulating ceramic layer adhered to the component by the bond coat, the component having a cooling hole that intersects the surface of the component, the cooling hole having a wall coated by contiguous portions of the bond coat and ceramic layer that extend into the cooling hole from the surface of the component, the portion of the ceramic layer being mechanically anchored to the cooling hole by compressive stresses; removing the ceramic layer from the surface of the component by subjecting the ceramic layer to a caustic solution at a temperature and pressure sufficient to cause the caustic solution to attack a chemical bond between the ceramic layer and the bond coat; and then removing the portion of ceramic layer from the cooling hole by directing into the cooling hole a fluid stream discharged from a source at a pressure of about 20,000 to about 60,000 psi through at least one nozzle having a diameter of about 0.005 to about 0.014 inch placed about 0.5 to about 3.0 inches from the wall of the cooling hole; wherein the step of removing the portion of ceramic layer from the cooling hole does not remove the bond coat from the wall of the cooling hole.