A method of forming a coating system on a surface of a superalloy component having film holes defined therein is provided. The method may include applying NiCoCrAlY on the surface of the superalloy component to form a NiCoCrAlY layer while keeping the film holes open (e.g., wherein the NiCoCrAlY layer has a chromium content that is higher than the superalloy component), then heating the NiCoCrAlY layer to a treatment temperature of about 900? C. to about 1200? C., then forming a platinum-group metal layer on the NiCoCrAlY layer, and then forming an aluminide coating over platinum-group metal layer. The NiCoCrAlY may be applied onto an existing coating system on the surface of the superalloy component, wherein the existing coating system is a Co-based coating system that is substantially free from Ni.

Unique and improved chromium coatings derived from modified chromium-containing slurry formulations are disclosed. The slurry formulation includes a combination of a selected halide activator and buffer material that synergistically interact with each other to form chromium diffusion coatings with improved microstructure in comparison to chromium diffusion coatings produced from conventional chromizing processes. The coatings may be locally applied in a controlled manner with accuracy onto various parts, including those having internal sections with complex geometries, without masking any portion thereof.

Unique and improved chromium coatings derived from modified chromium-containing slurry formulations are disclosed. The slurry formulation includes a combination of a selected halide activator and buffer material that synergistically interact with each other to form chromium diffusion coatings with improved microstructure in comparison to chromium diffusion coatings produced from conventional chromizing processes. The coatings may be locally applied in a controlled manner with accuracy onto various parts, including those having internal sections with complex geometries, without masking any portion thereof.

A coating process for applying a bifurcated coating to an article is disclosed including applying an aluminizing slurry to a first portion of the article, applying a chromizing slurry to a second portion of the article, and simultaneously heat treating the article, the aluminizing slurry, and the chromizing slurry. Heat treating the aluminizing slurry forms an aluminide coating on the first portion of the article and an aluminide diffusion zone between the article and the aluminide coating. Heat treating the chromizing slurry forms a chromide coating on the second portion of the article and a chromide diffusion zone between the article and the chromide coating. The first portion and the second portion are both maintained in an unmasked state while applying the aluminizing slurry and the chromizing slurry and during the heat treating.

A coating process for applying a bifurcated coating to an article is disclosed including applying an aluminizing slurry to a first portion of the article, applying a chromizing slurry to a second portion of the article, and simultaneously heat treating the article, the aluminizing slurry, and the chromizing slurry. Heat treating the aluminizing slurry forms an aluminide coating on the first portion of the article and an aluminide diffusion zone between the article and the aluminide coating. Heat treating the chromizing slurry forms a chromide coating on the second portion of the article and a chromide diffusion zone between the article and the chromide coating. The first portion and the second portion are both maintained in an unmasked state while applying the aluminizing slurry and the chromizing slurry and during the heat treating.

A masking apparatus for masking a part during coating and comprising at least two sintered pieces of a mask material. The pieces have an assembled condition forming a compartment shaped to accommodate an airfoil of the part. The pieces have an average overall composition of: nickel as a largest by-weight constituent; aluminum as a second largest by-weight constituent; and chromium as a third largest by-weight constituent.

A masking apparatus for masking a part during coating and comprising at least two sintered pieces of a mask material. The pieces have an assembled condition forming a compartment shaped to accommodate an airfoil of the part. The pieces have an average overall composition of: nickel as a largest by-weight constituent; aluminum as a second largest by-weight constituent; and chromium as a third largest by-weight constituent.

Unique and improved chromium coatings derived from modified chromium-containing slurry formulations are disclosed. The slurry formulation includes a combination of a selected halide activator and buffer material that synergistically interact with each other to form chromium diffusion coatings with improved microstructure in comparison to chromium diffusion coatings produced from conventional chromizing processes. The coatings may be locally applied in a controlled manner with accuracy onto various parts, including those having internal sections with complex geometries, without masking any portion thereof.

Unique and improved chromium coatings derived from modified chromium-containing slurry formulations are disclosed. The slurry formulation includes a combination of a selected halide activator and buffer material that synergistically interact with each other to form chromium diffusion coatings with improved microstructure in comparison to chromium diffusion coatings produced from conventional chromizing processes. The coatings may be locally applied in a controlled manner with accuracy onto various parts, including those having internal sections with complex geometries, without masking any portion thereof.

A process for applying a chromized layer on a substrate by first applying an overlay coating to a portion of the substrate, and subsequently contacting a different portion of the substrate and the overlay with a gas containing gaseous chromium, wherein the gaseous chromium can be generated from a chromium source and an activator. The process prepares the substrate, often a jet engine airfoil, for service.