Abstract:
A mask assembly for a gas turbine engine component includes a second mask that at least partially overlaps a first mask to fit a platform of a gas turbine engine component.
Abstract:
A method for treating a substrate prior to metallic coating includes the steps of providing a substrate having a surface to be coated and at least one contaminant selected from as-delivered organics and post-burn out oxides on the surface; treating the surface with a laser to remove the at least one contaminant to produce a cleaned surface on the substrate; and applying a metallic coating to the cleaned surface. Grit blasting can be avoided, and reverse arc transfer cleaning is avoided or minimized, resulting in time savings and less stress on the substrate.
Abstract:
A method for stripping ceramic from a component includes applying a liquid to a ceramic coating of an outer surface of the component. The method also includes directing a plurality of laser pulses at the ceramic coating with the applied liquid in order to spall the ceramic coating from the component.
Abstract:
A method of polishing an outer surface of a ceramic coated gas turbine engine component includes applying a rotating diamond brush to the outer surface. The brush is configured to achieve a uniform finish of 150 microinches RA or less over the surface. The brush contains diamond impregnated bristles, and is affixed to a rotary head of a robotic arm. A force sensing controller limits brush forces against the component. The component disclosed is a hot section turbine vane designed for directional control of high temperature, high-pressure combustion gases, but the method may be applied to other components utilized in similar aerospace applications. The polished coating provides an improved thermal barrier for maintaining structural integrity of the component in environments having temperatures ranging up to 2,000 degrees Celsius. The method limits abrasive removal of ceramic material to only 0.0005 to 0.00075 inch, and saves time and expense over past practices.
Abstract:
A mask assembly for a gas turbine engine component includes a second mask that at least partially overlaps a first mask to fit a platform of a gas turbine engine component.
Abstract:
Non-stick fixtures for selectively masking portions of a workpiece during application of a workpiece coating are described herein. These fixtures have predetermined surfaces thereon having an average surface roughness of about 25 Ra or less and a Rockwell hardness of about 65 Rc or more. The controlled average surface roughness ensures that these fixtures are non-stick with respect to the workpiece coating being applied to the workpieces disposed therein. The controlled Rockwell hardness ensures that the desired average surface roughness can be maintained throughout repeated use of the fixture in harsh coating environments. These fixtures reduce the workpiece coating bridging that occurs between the fixture and the workpiece, and also reduce the amount of overspray that occurs on the workpiece, thereby minimizing the amount of handwork and/or rework that is necessary after the workpiece is coated. This improves process cycle times and yields significantly.
Abstract:
A method for stripping ceramic from a component includes applying a liquid to a ceramic coating of an outer surface of the component. The method also includes directing a plurality of laser pulses at the ceramic coating with the applied liquid in order to spall the ceramic coating from the component.
Abstract:
A method of polishing an outer surface of a ceramic coated gas turbine engine component includes applying a rotating diamond brush to the outer surface. The brush is configured to achieve a uniform finish of 150 microinches Ra or less over the surface. The brush contains diamond impregnated bristles, and is affixed to a rotary head of a robotic arm. A force sensing controller limits brush forces against the component. The component disclosed is a hot section turbine vane designed for directional control of high temperature, high-pressure combustion gases, but the method may be applied to other components contained within such aerospace applications. The polished coating provides an improved thermal barrier for maintaining structural integrity of the component in environments having temperatures ranging up to 2,000 degrees Celsius. The method limits abrasive removal of ceramic material to only 0.0005 to 0.00075 inch, and saves time and expense over past practices.
Abstract:
Non-stick fixtures for selectively masking portions of a workpiece during application of a workpiece coating are described herein. These fixtures have predetermined surfaces thereon having an average surface roughness of about 25 Ra or less and a Rockwell hardness of about 65 Rc or more. The controlled average surface roughness ensures that these fixtures are non-stick with respect to the workpiece coating being applied to the workpieces disposed therein. The controlled Rockwell hardness ensures that the desired average surface roughness can be maintained throughout repeated use of the fixture in harsh coating environments. These fixtures reduce the workpiece coating bridging that occurs between the fixture and the workpiece, and also reduce the amount of overspray that occurs on the workpiece, thereby minimizing the amount of handwork and/or rework that is necessary after the workpiece is coated. This improves process cycle times and yields significantly.