BACKGROUND

The present invention is directed toward a turbine component coating process and a turbine component. More specifically, the present invention is directed to a turbine component coating process including the use of protective shields, and a turbine component including the application of a coating employing the protective shields.

BACKGROUND OF THE INVENTION

Turbine components are often run at high temperatures to provide maximum operating efficiency. However, the temperature at which a turbine can run may be limited by the temperature capabilities of the individual turbine components. In order to increase the temperature capabilities of turbine components, various methods have been developed. One method for increasing the temperature capabilities of a turbine component includes the incorporation of internal cooling holes, through which cool air is forced during turbine engine operation. As cooling air is fed from the cooler side of the component wall through a cooling hole outlet on the hot side, the rushing air assists in lowering the temperature of the hot metal surface.

Another technique for increasing the temperature capabilities of a turbine component includes the application of coatings, such as a bond coat and a thermal barrier coating (TBC). Often, turbine components include both cooling holes and various coatings applied over the surface of the component. Typically, when cooling holes are formed or modified (e.g., repaired) in the component prior to the (re)application of the coatings, the cooling holes are either masked before coating or the coating is removed from the cooling holes after application. More particularly, conventional methods provide for cooling holes to be drilled in bare metal and then coated with TBC. In many instances, these holes suffer from poor performance caused by the partial filling with TBC and changes to the desired shape of the hole. Additionally, variation in the application of the TBC to the holes can cause unpredictable performance. Alternatively, the coating may be applied first, and then cooling holes are drilled. However, this may require an additional manufacturing step to remove the coating so that holes can be formed. The resulting part may then lack some TBC protection in important regions, such as the trailing edge.

Accordingly, a turbine component coating process with improvements would be desirable in the art.

BRIEF DESCRIPTION OF THE INVENTION

Aspects and advantages of the disclosure are set forth below in the following description, or may be obvious from the description, or may be learned through practice of the disclosure.

In accordance with one embodiment, a method of depositing a coating on a component of a turbine engine is disclosed. The method includes forming a turbine component including at least one cooling flow passage in fluid communication with an aperture on a surface of the turbine component, forming a protective shield on an inner surface of the at least one cooling flow passage and extending to an exterior of the turbine component via the aperture, depositing a coating on an exterior surface of the turbine component, wherein the protective shield is configured to block the coating from being deposited in the at least one cooling flow passage via the aperture. Finally, at least a portion of the protective shield is removed to provide for passage of a cooling fluid flow in the at least one cooling flow passage and wherein the cooling fluid flow exits the turbine component through the aperture.

In another embodiment, method of depositing a coating on a component of a turbine engine is disclosed. The method includes forming via an additive manufacturing process a turbine component including at least one cooling flow passage in fluid communication with an aperture on a surface of the turbine component and a protective shield coupled to an inner surface of the at least one cooling flow passage and extending to an exterior of the turbine component via the aperture. A coating is next deposited on an exterior surface of the turbine component, wherein the protective shield blocks the coating from being deposited in the at least one cooling flow passage. Finally, at least a portion of the protective shield is removed to provide for passage of a cooling fluid flow in the at least one cooling flow passage and wherein the cooling fluid flow exits the turbine component through the aperture.

In yet another embodiment, a turbine component is disclosed. The turbine component includes at least one cooling flow passage having an inner surface and defining a flow path for the passage there through of a cooling fluid flow, a portion of a protective shield on one of the inner surface of the at least one cooling flow passage and an exterior surface of the turbine component in a manner to provide deflection of a cooling fluid flow exiting the aperture and a coating deposited on an exterior surface of the turbine component. The at least one aperture is formed in a surface of the component and in fluid communication with the at least one cooling flow passage. A cooling fluid flow in the at least one cooling flow passage exits the turbine component through the aperture.

Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention. These and other features, aspects and advantages of the present disclosure will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.

