Abstract: Process of masking cooling holes of a gas turbine component with an external surface, comprising a cavity and a plurality of cooling holes before coating the gas turbine component, comprising the steps of first applying a mask material to the cooling holes so that the cooling holes are filled at least closest to the external surface, whereby the mask material contains a substance which fluoresces under ultraviolet light and a filler material. Then the mask material within the cooling holes is thickening. An inspection using ultraviolet light to locate any unwanted residual mask material on the external surface is carried out and unwanted residual mask material is removed before the coating is applied to the external surface of the component and the masked cooling holes. In the end the mask material is removed from the cooling holes.

Abstract: A method is disclosed for recovering the properties of single crystal and directionally solidified Nickel based superalloys and articles made thereof, after use in a high temperature environment. The method comprises the steps of a stress relief treatment, a ?? rejuvenation heat treatment at a temperature below the ??-solvus temperature (Tsolvus, ??) of the superalloy, a precipitation heat treatment and an aging heat treatment.

Abstract: A method for repairing or renewing cooling holes of a coated component of a gas turbine, includes the step of removing an old coating from an outer side of the component. The cooling hole, after removing the old coating, in a longitudinal section, has an old cross section which is larger than a nominal cross section which the cooling hole has in this longitudinal section in an original new state of the finished component. The method also includes applying a new coating to the component at least in the longitudinal section of the cooling hole so that the cooling hole, in the longitudinal section, has an interim cross section which is smaller than the nominal cross section. The method also includes partially removing the new coating inside the cooling hole so that the cooling hole, in the longitudinal section, has a new cross section which is about the same size as the nominal cross section.

Abstract: A method and an apparatus for manufacturing a directionally solidified columnar grained article with a reduced amount of secondary misorientation of the columnar grains. The method employs a casting assembly comprising a mold with a cavity, a selector section at a lower end of the mold, a heating chamber and a cooling chamber. The mold is fed with a liquid metal and moved from the heating chamber to the cooling chamber where the columnar grained article is solidified. The article is solidified with at least two dendrites or grains emerging from the selector section and entering the main cavity of the shell mold. Further, the selector section is configured so that no dendrite or grain grows from the bottom of the selector section into the shell mold cavity along a continuous path of purely vertical growth.

Abstract: An apparatus for manufacturing a directionally solidified columnar grained article with a reduced amount of secondary misorientation of the columnar grains. The apparatus includes a casting assembly comprising a mold with a cavity, a selector section at a lower end of the mold, a heating chamber and a cooling chamber. The mold is fed with a liquid metal and then moved from the heating chamber to the cooling chamber where the columnar grained article is solidified. The article is solidified with at least two dendrites (or grains) emerging from the selector section and entering the main cavity of the shell mold. Further, the selector section is configured so that no dendrite or grain grows from the bottom of the selector section into the shell mold cavity along a continuous path of purely vertical growth.

Abstract: Process of masking cooling holes of a gas turbine component with an external surface, comprising a cavity and a plurality of cooling holes before coating the gas turbine component, comprising the steps of first applying a mask material to the cooling holes so that the cooling holes are filled at least closest to the external surface, whereby the mask material contains a substance which fluoresces under ultraviolet light and a filler material. Then the mask material within the cooling holes is thickening. An inspection using ultraviolet light to locate any unwanted residual mask material on the external surface is carried out and unwanted residual mask material is removed before the coating is applied to the external surface of the component and the masked cooling holes. In the end the mask material is removed from the cooling holes.

Abstract: A method for removing casting defects (5) from an article (1) with an oriented microstructure can include locating at least one casting defect (5) and melting the casting defect (5) locally by a heat source (7) to a depth at least as great as the casting defect (5) itself. The molten material can then be solidified epitaxially with respect to the surrounding oriented microstructure of the article (1) in a way that the resulting solidified area is substantially free of any defect.

Abstract: A process of masking cooling holes (4) of a gas turbine component (1) with an external surface (6), including a cavity (2) and a plurality of cooling holes (4) before coating the gas turbine component (1), includes first applying a mask material (5) to the cooling holes (4) so that the cooling holes are filled at least closest to the external surface (6), whereby the mask material (5) contains a filler material. Then the mask material (5) within the cooling holes (4) is thickening and the coating (8) is applied to the external surface (6) of the component (1) and the masked cooling holes (4). In the end remaining thickened mask material (5a) is removed from the cooling holes (4).

Abstract: Process of masking cooling holes of a gas turbine component with an external surface, comprising a cavity and a plurality of cooling holes before coating the gas turbine component, comprising the steps of first applying a mask material to the cooling holes so that the cooling holes are filled at least closest to the external surface, whereby the mask material contains a substance which fluoresces under ultraviolet light and a filler material. Then the mask material within the cooling holes is thickening. An inspection using ultraviolet light to locate any unwanted residual mask material on the external surface is carried out and unwanted residual mask material is removed before the coating is applied to the external surface of the component and the masked cooling holes. In the end the mask material is removed from the cooling holes.

Abstract: It is disclosed a method of protecting a local area of components (1) from the effects of thermochemical or mechanical processes carried out on the surface (6) of the component. A masking material (5) containing at least one filler material is applied to the local area so that the local area is protected by the masking material (5). This is at least partially polymerized on the local area. Subsequently the thermochemical or physical processes on the surface (6) of the component (1) are carried out after which the polymerized masking material (5) is removed from the local area of the component (1).

Abstract: Process of masking cooling holes of a gas turbine component with an external surface, comprising a cavity and a plurality of cooling holes before coating the gas turbine component, comprising the steps of first applying a mask material to the cooling holes so that the cooling holes are filled at least closest to the external surface, whereby the mask material contains a substance which fluoresces under ultraviolet light and a filler material. Then the mask material within the cooling holes is thickening. An inspection using ultraviolet light to locate any unwanted residual mask material on the external surface is carried out and unwanted residual mask material is removed before the coating is applied to the external surface of the component and the masked cooling holes. In the end the mask material is removed from the cooling holes.

Abstract: A method is disclosed for recovering the properties of single crystal and directionally solidified Nickel based superalloys and articles made thereof, after use in a high temperature environment. The method comprises the steps of a stress relief treatment, a ?? rejuvenation heat treatment at a temperature below the ??-solvus temperature (Tsolvus, ??) of the superalloy, a precipitation heat treatment and an aging heat treatment.

Abstract: A process of masking cooling holes (4) of a gas turbine component (1) with an external surface (6), including a cavity (2) and a plurality of cooling holes (4) before coating the gas turbine component (1), includes first applying a mask material (5) to the cooling holes (4) so that the cooling holes are filled at least closest to the external surface (6), whereby the mask material (5) contains a filler material. Then the mask material (5) within the cooling holes (4) is thickening and the coating (8) is applied to the external surface (6) of the component (1) and the masked cooling holes (4). In the end remaining thickened mask material (5a) is removed from the cooling holes (4).

Abstract: It is disclosed a method of protecting a local area of components (1) from the effects of thermochemical or mechanical processes carried out on the surface (6) of the component. A masking material (5) containing at least one filler material is applied to the local area so that the local area is protected by the masking material (5). This is at least partially polymerized on the local area. Subsequently the thermochemical or physical processes on the surface (6) of the component (1) are carried out after which the polymerized masking material (5) is removed from the local area of the component (1).

Abstract: It is a method of repairing a ceramic coating of an article after use of this article in a high temperature environment disclosed. The ceramic coating is removed locally at spalled areas, at the areas where the ceramic coating is removed locally a mixture including a powder of zirconia stabilized with one or a combination of yttria, calcia, scandia, magnesia, ceria and oxides of the rare earth group, and hydrated metallic halides as a binder is applied and the applied ceramic powder is dried.

Abstract: A method of repairing cracks on a surface of a component such as gas turbine components includes the steps of repairing the cracks of the component by brazing, detecting remaining cracks on the surface or below the surface, which were not properly filled with braze material during the repair brazing operation, and repairing the crack zones with a focussed low-heat input welding method using an appropriate weld filler materials.

Abstract: A method for removing casting defects (5) from an article (1) with an oriented microstructure can include locating at least one casting defect (5) and melting the casting defect (5) locally by a heat source (7) to a depth at least as great as the casting defect (5) itself. The molten material can then be solidified epitaxially with respect to the surrounding oriented microstructure of the article (1) in a way that the resulting solidified area is substantially free of any defect.

Abstract: An apparatus for manufacturing a directionally solidified columnar grained article with a reduced amount of secondary misorientation of the columnar grains. The apparatus includes a casting assembly comprising a mold with a cavity, a selector section at a lower end of the mold, a heating chamber and a cooling chamber. The mold is fed with a liquid metal and then moved from the heating chamber to the cooling chamber where the columnar grained article is solidified. The article is solidified with at least two dendrites (or grains) emerging from the selector section and entering the main cavity of the shell mold. Further, the selector section is configured so that no dendrite or grain grows from the bottom of the selector section into the shell mold cavity along a continuous path of purely vertical growth.

Abstract: A tip material for a turbine blade or for repairing a damaged tip of a turbine blade having a metallic coating, the material used for the tip is equivalent in composition to the metallic coating material used for the turbine blade. Also disclosed is a method of manufacturing or repairing a tip of a turbine blade having a metallic coating by reforming the blade tip with a material equivalent in composition to the metallic coating material used for the turbine blade by bonding the material to the damaged tip.

Abstract: A process for the rapid production of hollow components of flow machines, in particular turbine blades, for manufacturing development. In the process, the turbine blade to be produced is divided into two or more portions such that none of the portions has a cavity. The two or more portions are individually cast by means of a Rapid Prototype process, and are then joined together to form the hollow component. The process makes possible the simple and cost-effective production of turbine blades for manufacturing development, in particular for the development of the cooling systems.