摘要:
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.
摘要:
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.
摘要:
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 then removed 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.
摘要:
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.
摘要:
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.
摘要:
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).
摘要:
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).
摘要:
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.
摘要:
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.
摘要:
A method of applying a surface coating to a stator vane (1) of a gas turbine, the stator vane (1) comprising a platform (3) with an outer surface (4) connected to the stator of the gas turbine and an airfoil (2) connected to the platform (3), the method comprising the steps of each stator vane (1) is provided as a singlet, a base layer coating (7) affording resistance to oxidation is applied to surfaces of said stator vane (1) and said outer surface (4) of the platform (3) to be exposed to hot gases of the gas turbine, and a top layer coating (8) affording thermal resistance is applied to all coated surfaces of said stator vane (1) and the outer surface (4) of the platform (3), and welding the stator vanes (1) together, wherein a welding filler material (10) is placed between said walls of two adjacent platforms (3) of said stator vane (1), welding said singlets to one another at the margins of walls of said platform (3) to said welding filler material (10).