Method for removing an environmental coating

A method for removing an environmental coating on a metallic substrate, the method comprising the steps of:

• providing a metallic substrate having a diffusion aluminide coating comprising an aluminide-containing additive layer and a diffusion zone between the additive layer and the substrate;
• mechanically peening the diffusion aluminide coating at a temperature less than the ductile-to-brittle transition temperature thereof so as to form cracks through the additive layer;
• and then
• subjecting the diffusion aluminide coating to an acidic solution that penetrates the cracks and interacts with the diffusion zone so as to chemically strip the diffusion aluminide coating from the substrate.

A method for removing an environmental coating on a component of a gas turbine engine, the method comprising the steps of:

• providing a gas turbine engine component having a diffusion aluminide coating comprising an aluminide-containing additive layer and a diffusion zone;
• shot peening the diffusion aluminide coating at a temperature less than the ductile-to-brittle transition temperature thereof so as to form cracks that extend through the additive layer to the diffusion zone;
• and then
• subjecting the diffusion aluminide coating to an acidic solution at approximately room temperature, the acidic solution penetrating the cracks and interacting with the diffusion zone so as to chemically strip the diffusion aluminide coating from the component.