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: The invention relates to a process of repairing a MCrAlY-coating of an article, which has being exposed to the hot gases of, for example, a gas turbine. The MCrAlY-coating is examined and repaired only locally where it is needed and then, subsequently, on top of the MCrAlY-coating the article is aluminized and/or chromized, avoiding the stripping of the whole coating and re-coating over the entire surface of the article. This is for replenishing the coating of Al and/or Cr that become depleted during engine operation, in an easy, cost and time saving manner.

Abstract: A process of brazing cracks and gaps in a single crystal article which takes places isothermally under the following conditions: the temperature of the isothermal solidification is between TLiqidus, Braze+5*(wt-%BBraze) and (Tsolidus, base material−70*(wt-%BBraze)), while (wt-% B*wt-%Cr) is between 15 and 40 and (Tsolv.&ggr;′, base material−TLiqidus, Braze) is above 140° C. This results in an homogeneous &ggr;/&ggr;′-microstructure of the isothermal solidified, brazed joint with mechanical properties similar to those of the base material.

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 nickel-base superalloy, in particular for the production of single-crystal components or directionally solidified components, comprising (measured in % by weight): 3.0-13.0% Cr, 5.0-15.0% Co, 0-3.0% Mo, 3.5-9.5% W, 3.2-6.0% Al, 0-3.0% Ti, 2.0-10.0% Ta, 0-6.0% Re, 0.002-0.08% C, 0-0.04% B, 0-1.4% Hf, 0-0.005% Zr, 10-60 ppm N, remainder nickel plus impurities. As a result of the addition of nitrogen in defined quantities, TiN is formed during solidification and carbides with a block morphology are formed. It is thus possible to increase the carbon content without deterioration in the low cycle fatigue at high load temperature.

Abstract: Method for producing or repairing cooling channels (7a) of a gas turbine component (1), whereby the cooling channels (7a) are masked with a thermally stable filling material (3) on the cast gas turbine component (1), and another epitactic layer (6) is created above the ceramic material (3) with the help of a laser (4) and a powder (5). The thermally stable filling material (3) is removed by etching.

Abstract: A nickel base alloy comprising: (measured in % by weight): 11-16% Co; 12.2-15.5% Cr; 6.5-7.2% Al; 3.2-5.0% Re; 1.0-2.5% Si; 1.5-4.5% Ta; 0.2-2.0% Nb; 0.2-1.2% Hf; 0.2-1.2% Y; 0-1.5% Mg; 0-1.5% Zr; 0-0.5% La and La series elements; 0-0.15% C; 0-0.1% B; and a remainder including Ni and impurities. The alloy is particularly suited for coatings for gas turbine components such as gas turbine blades and vanes.

Abstract: The invention relates to a process of repairing a MCrAlY-coating of an article, which has being exposed to the hot gases of, for example, a gas turbine. The MCrAlY-coating is examined and repaired only locally where it is needed and then, subsequently, on top of the MCrAlY-coating the article is aluminized and/or chromized, avoiding the stripping of the whole coating and re-coating over the entire surface of the article. This is for replenishing the coating of Al and/or Cr that become depleted during engine operation, in an easy, cost and time saving manner.

Abstract: A method of casting a directionally solidified article such as a component of a gas or steam turbine. The casting is performed in a casting furnace comprising a heating chamber, a liquid cooling bath as a cooling chamber and a shell mold. During casting, shell mold is fed with liquid metal and withdrawn from the heating chamber to the cooling chamber while the interior of the casting furnace is supplied with an inert atmosphere of Ar and/or He in the pressure range of 0.01 to 1 atmosphere, with a preferred range of 0.05 to 0.25 atmosphere. The method can provide improved heat transfer across the shell mold allowing a higher withdrawal rate, reduction in defects and/or improvement in properties of the cast articles.

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.

Abstract: A coating composition for superalloy structural parts, especially, for gas turbine vanes and blades, which has high resistance to oxidation and corrosion and has excellent mechanical behavior. The coating preferably comprises: 18 to 28 wt % of Co; 11 to 15 wt % of Cr; 11.5 to 14 wt % of Al; 1 to 8 wt % of Re; 1 to 2.3 wt % of Si; 0.2 to 1.5 wt % of Ta; 0.2 to 1.5 wt % of Nb; 0.3 to 1.3 wt % of Y; 0 to 1.5 wt % of Mg; 0 to 0.5 wt % of a total of La and La-series; 0 to 0.1 wt % of B; less than 0.1 wt % of Hf; and less than 0.1 wt % of C. The balance of the coating is Ni. A total of Y, La, and La-series is from 0.3 to 2.0 wt %, and a total of Si and Ta is equal to or less than 2.5 wt %.

Abstract: A gas turbine component consists of a superalloy base material with a single crystal structure and a protective coating layer. The coating layer has a single crystal structure, which is epitaxial with the base material.

Abstract: The invention relates to a coating composition for superalloy structural parts, especially for gas turbine vanes and blades, which provides simultaneously excellent environmental resistance and highly improved thermomechanical behavior. The coating consists essentially of, by weight, 28-35% Co, 11-15% Cr, 10-13% Al, 0-1% Re, 1-2% Si, 0.2-1% Ta, 0.005-0.5% Y, 0-5% Ru, 0-1% Ca, 0-1% Mg, 0-0.5% La (or elements from the La series), 0-0.1% B, balance Ni and incidental impurities.

Abstract: The process serves to produce a directionally solidified casting (20) and uses an alloy located in a casting mold (12). The casting mold (12) is guided from a heating chamber (4) into a cooling chamber (5). The heating chamber (4) is here at a temperature above the liquidus temperature of the alloy, and the cooling chamber (5) is at a temperature below the solidus temperature of the alloy. The heating chamber (4) and the cooling chamber (5) are separated from one another by a baffle (3), aligned transversely to the guidance direction, having an opening (7) for the casting mold (12). When carrying out the process, a solidification front (19) is formed, beneath which the directionally solidified casting (20) is formed. The part of the casting mold (12) which is guided into the cooling chamber (5) is cooled with a flow of inert gas. As a result, castings (20) which are practically free of defects are achieved with high throughput times.

Abstract: A nickel-base superalloy, in particular for the fabrication of monocrystalline components, consisting essentially of (measured in wt %) 6.0-6.8% of Cr, 8.0-10.0% of Co, 0.5-0.7% of Mo, 6.2-6.6% of W, 2.7-3.2% of Re, 5.4-5.8% of Al, 0.5-0.9% of Ti, 7.2-7.8% of Ta, 0.15-0.3% of Hf. 0.02-0.04% of C, 40-100 ppM of B, the remainder being nickel with impurities. The ratio (Ta+1.5 Hf+0.5 Mo-0.5 Ti)/(W+1.2 Re) is greater than or equal to 0.7.

Abstract: In a heat treatment process for material bodies made of nickel base superalloys, in particular for monocrystals made of nickel base superalloys, the heat treatment of the material body comprises the following steps: annealing at 850.degree. C. to 1100.degree. C., heating to 1200.degree. C., heating to a temperature of 1200.degree. C.<T.ltoreq.1300.degree. C. at a heat-up rate of less than or equal to 1.degree. C./min, and a multistage homogenization and dissolution process at a temperature of 1300.degree. C..ltoreq.T.ltoreq.1315.degree. C.

Abstract: A nickel-base superalloy, in particular for the fabrication of large monocrystalline components, essentially comprises (measured in wt %): 6.0-6.8% of Cr, 8.0-10.0% of Co, 0.5-0.7% of Mo, 6.2-6.6% of W, 2.7-3.2% of Re, 5.4-5.8% of Al, 0.6-1.2% of Ti, 6.3-7.0% of Ta, 0.15-0.3% of Hf, 0.02-0.04% of C, 40-100 ppm of B. 15-50 ppm of Mg, the remainder being nickel with impurities. Carbides of Ta, Ti, and Hf, and Mg, and/or Mg--O--S compounds are concentrated along small angle grain boundaries of the superalloy.