Abstract: A nickel-base alloy composition includes nickel as the main constituent and the further constituents in percent by weight (% by weight): 0.04 to 0.10% carbon (C), 8 to 13% tantalum (Ta), 12 to 20% chromium (Cr), 3 to 25% cobalt (Co), less than 0.03% manganese (Mn), less than 0.06% silicon (Si), 0 to 6% molybdenum (Mo), less than 5.0% iron (Fe), 2 to 4% aluminum (Al), less than 0.01% magnesium (Mg), less than 0.02% vanadium (V), 0 to 6% tungsten (W), less than 1% titanium (Ti), less than 0.03% yttrium (Y), 0.005 to 0.015% boron (B), less than 0.003% sulfur (S), 0.005 to 0.04% zirconium (Zr) and less than 3% hafnium. Additionally provided are an additive manufacturing method, a method of additively manufacturing a component part from a powder of the alloy composition provided, a corresponding intermediate alloy, and a component part consisting of the nickel-base superalloy.

Abstract: A method of producing or repairing single-crystalline turbine or engine components by the following steps: heating of braze filler metal to a temperature which is greater than or equal to the melting temperature of the braze filler metal; introducing the molten mass of the braze filler metal produced through the heating process into a crack formed in the turbine or engine component, or into the gap formed between two turbine or engine components, or into a damaged area of a turbine or engine component; and non-isothermal control or regulation of the temperature of the braze filler metal or turbine or engine component during an epitaxic solidification process of the braze filler metal.

Abstract: A method for machining a workpiece made from titanium based alloy is provided. the method comprises: heating the workpiece in a hydrogen containing atmosphere, whereby hydrogen is taken up; cooling the workpiece; metal-removing machining of the workpiece; and heating the workpiece in a hydrogen-free atmosphere, whereby hydrogen is released. A workpiece made by the method is also provided.

Abstract: It is disclosed a method for strengthen the grain boundaries of an article (1) made from a Ni based superalloy while the article (1) is in the solid state and containing at least one grain boundary. A surface diffusion process is applied to the article (1) to enrich the at least one grain boundary with grain boundary strengthening elements of one or a combination of boron, hafnium, zirconium without forming brittle precipitates like borides or carbides.

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: An iron-nickel superalloy of the type IN 706 has an addition of 0.02 to 0.3 percent by weight of boron and/or 0.05 to 1.5 percent by weight of hafnium. By means of this addition, a virtual doubling of the ductility is achieved as compared with an addition-free iron-nickel superalloy of the type IN 706, while the hot strength is reduced only slightly. The alloy is particularly suitable as a material for rotors of large gas turbines. It has a sufficiently high hot strength. When locally acting temperature gradients arise unwanted stresses can occur to only a slight extent because of the high ductility of the alloy.

Abstract: The method serves to produce a material based on a doped intermetallic compound. In carrying out the method, at least two differently doped powders each based on the intermetallic compound are selected. One of the two powders predominantly has coarse-grained particles. On the other hand, another powder is formed from comparatively fine-grained particles composed of a material having a lower creep strength but a higher ductility than the material of the coarse-grained powder. The at least two powders are mixed with one another in a ratio serving to establish a desired mixed microstructure and then hot-compacted and heat-treated to form the material.Material produced by this method is suitable for components which are exposed to high mechanical loads at high temperatures, such as, in particular, gas-turbine blades or turbine wheels of turbo chargers.

Abstract: A turbine blade including a blade and blade foot. The blade foot is formed by a ductile material and the blade comprises a material which is brittle compared to the ductile material but resistant to high temperature. The two materials are alloys of the same base compositions but differ as to presence and/or quantity of at least one doping element. The alloys can be hot-compacted with the formation of a transition zone joining the blade and blade root wherein fine crystallites of the blade root interpenetrate coarse crystallites of the blade. The two materials can comprise a gamma-titanium aluminide containing 0.5 to 8 atomic percent of a dopant. The turbine blade exhibits outstanding mechanical properties at high temperatures, good ductility at room temperature and a long service life.