Abstract: The invention relates to a method for welding rotors for power generation such as gas turbines, steam turbines, and generators having a plurality of rotor discs arranged along a rotor axis. The method includes providing said discs with a weld seam preparation. The weld seam preparation includes a root, a first, gap-like welding section adjoining the root in radial direction, and a second, gap-like welding section adjoining the first welding section in radial direction. The method further includes melting the root by means of a first welding process; making a weld in the first welding section by means of a second welding process; and filling up the second welding section by means of a third welding process.

Abstract: A nickel-base superalloy is characterized by the following chemical composition (details in % by weight): 7.7-8.3 Cr, 5.0-5.25 Co, 2.0-2.1 Mo, 7.8-8.3 W, 5.8-6.1 Ta, 4.9-5.1 Al, 1.0-1.5 Ti, 1.0-2.0 Re, 0.11-0.15 Si, 0.1-0.7 Hf, 0-0.5 Nb, 0.02-0.17 C, 50-400 ppm B, remainder Ni and production-related impurities. The alloy is distinguished by a very high resistance to oxidation, resistance to corrosion and good creep properties at high temperatures.

Abstract: A rotor blade (10) for a gas turbine includes a blade airfoil (11), a blade tip (15), a blade root (14), and a platform (12) which is formed between the blade tip (15) and the blade root (14), and is assembled from a plurality of individual sections (16, 17, 18), the material of which is adapted in each case to the intended purpose of the individual section concerned. With such a rotor blade, a simplified production is achieved as a result of each of the individual sections (16, 17, 18) from the dimensions being significantly smaller than the assembled rotor blade (10).

Abstract: The invention relates to a method for welding rotors for power generation such as gas turbines, steam turbines, and generators having a plurality of rotor discs arranged along a rotor axis. The method includes providing said discs with a weld seam preparation. The weld seam preparation includes a root, a first, gap-like welding section adjoining the root in radial direction, and a second, gap-like welding section adjoining the first welding section in radial direction. The method further includes melting the root by means of a first welding process; making a weld in the first welding section by means of a second welding process; and filling up the second welding section by means of a third welding process.

Abstract: A nickel-base superalloy with improved degradation behavior consists essentially of the following chemical composition (details in % by weight): 7.7-8.3 Cr, 5.0-5.25 Co, 2.0-2.1 Mo, 7.8-8.3 W, 5.8-6.1 Ta, 4.9-5.1 Al, 1.3-1.4 Ti, 0.1-0.6 Pt, 0.1-0.5 Nb, 0.11-0.15 Si, 0.11-0.15 Hf, 200-750 ppm C, 50-400 ppm B, and the remainder Ni and production-related impurities.

Abstract: A filler material for welding is characterized by the following chemical composition (amounts in % by weight): 0.05-0.15 C, 8-11 Cr, 2.8-6 Ni, 0.5-1.9 Mo, 0.5-1.5 Mn, 0.15-0.5 Si, 0.2-0.4 V, 0-0.04 B, 1-3 Re, 0.001-0.07 Ta, 0.01-0.06 N, 0-60 ppm Pd, max. 0.25 P, max. 0.02 S, remainder Fe and manufacturing-related unavoidable impurities. The material has outstanding properties, in particular a good creep rupture strength/creep resistance, a good oxidation resistance and a very high toughness.

Abstract: A nickel-base superalloy is characterized by the following chemical composition (details in % by weight): 7.7-8.3 Cr, 5.0-5.25 Co, 2.0-2.1 Mo, 7.8-8.3 W, 5.8-6.1 Ta, 4.9-5.1 Al, 1.0-1.5 Ti, 1.0-2.0 Re, 0.11-0.15 Si, 0.1-0.7 Hf, 0-0.5 Nb, 0.02-0.17 C, 50-400 ppm B, remainder Ni and production-related impurities. The alloy is distinguished by a very high resistance to oxidation, resistance to corrosion and good creep properties at high temperatures.

Abstract: A nickel-base superalloy with improved degradation behavior consists essentially of the following chemical composition (details in % by weight): 7.7-8.3 Cr, 5.0-5.25 Co, 2.0-2.1 Mo, 7.8-8.3 W, 5.8-6.1 Ta, 4.9-5.1 Al, 1.3-1.4 Ti, 0.1-0.6 Pt, 0.1-0.5 Nb, 0.11-0.15 Si, 0.11-0.15 Hf, 200-750 ppm C, 50-400 ppm B, and the remainder Ni and production-related impurities.

Abstract: A rotor blade (10) for a gas turbine includes a blade airfoil (11), a blade tip (15), a blade root (14), and a platform (12) which is formed between the blade tip (15) and the blade root (14), and is assembled from a plurality of individual sections (16, 17, 18), the material of which is adapted in each case to the intended purpose of the individual section concerned. With such a rotor blade, a simplified production is achieved as a result of each of the individual sections (16, 17, 18) from the dimensions being significantly smaller than the assembled rotor blade (10).

Abstract: The invention relates to an axial-flow thermal turbomachine having a metallic rotor (1), in which rotor blades (3) made of an intermetallic compound are mounted in a circumferential groove to form a row of blades. The invention is characterized in that at least two rotor blades (3?) which are at a uniform distance from one another and are made of a more ductile material are arranged in the said row of blades between the intermetallic rotor blades (3), the rotor blades (3?) made of the more ductile material either being considerably longer than the intermetallic blades (3) or, if they are of the same length, having a different blade tip shape than the intermetallic blades (3).

Abstract: The invention relates to an axial-flow thermal turbomachine, having a rotor (1) made from a metallic material with a first density (D1), in which rotor blades (3, 3?) and intermediate pieces (4) are mounted alternately in a circumferential groove. It is characterized in that said intermediate pieces (4) consist of a material with a second density (D2), which is lower than the first density (D1). Particularly suitable materials for the intermediate pieces (4) are intermetallic compounds, preferably intermetallic ?-titanium aluminide alloys or intermetallic orthorhombic titanium aluminide alloys, but also titanium alloys.