| 摘要 |
A method is provided for refurbishing a service operated metallic coating (12) on a substrate alloy (10), the coating (12) including at least within a coating outer surface (16) at least one oxide (14) chemically grown from at least one coating element, for example Al, and chemically bonded with the coating outer surface (16) as a result of thermal exposure during service operation. Growth of the oxide (14) has depleted at least a portion of the coating element from the coating (12). The method comprises removing the oxide (14) from the coating outer surface while substantially retaining the metallic coating (12), thereby exposing in the coating outer surface at least one surface void that had been occupied by the oxide (14). The retained metallic coating (12) is mechanically worked, substantially without removal of the retained coating (12), to close the void, providing a treated metallic coating surface over which a refurbishing coating (22) is applied. In one form, the mechanical working provides, concurrently, a compressive stress in the substrate alloy (10) beneath the metallic coating (12). <IMAGE> <IMAGE> |
