Abstract: A welded component includes at least one high temperature segment of a high alloy Cr steel with high creep strength and a low temperature segment of a low alloy steel with high toughness and/or a high yield strength which are connected materially to one another via a weld joint. In one such component a gradual transition of chemical, physical and mechanical properties in the joining area is achieved in that between the weld joint and the high temperature segment there are at least two successive clad layers of at least two lower alloy weld metals with a total content of elements which increase the creep strength, such as for example Cr, Mo, W and V, which total content decreases toward the weld joint, and/or an increasing total content of elements which increase the toughness and/or yield strength, such as for example Ni and Mn, which total content increases toward the weld joint.

Abstract: A metallic component includes a base material (1) and a coating that is deposited on the surface of its base material (1) and protects the component from oxidation and/or corrosion. The coating includes two oxidation resistant layers (2,4). The second oxidation resistant layer (4) includes a sol-gel that forms a uniform film (4) on the surface of the first layer (2) and fills any cracks (3) that extend from the surface of the first oxidation resistant layer (2). The first oxidation resistant layer (2) in combination with the sol-gel layer (4) provides an improved high temperature oxidation resistance of the metallic component as the sol-gel (4) prevents oxidizing media from reaching the base material (1) through cracks propagating through the first coating layer (2). As an option, an additional innermost layer of MCrAlY may be applied on the surface of the base material (1).

Abstract: A welded component includes at least one high temperature segment of a high alloy Cr steel with high creep strength and a low temperature segment of a low alloy steel with high toughness and/or a high yield strength which are connected materially to one another via a weld joint. In one such component a gradual transition of chemical, physical and mechanical properties in the joining area is achieved in that between the weld joint and the high temperature segment there are at least two successive clad layers of at least two lower alloy weld metals with a total content of elements which increase the creep strength, such as for example Cr, Mo, W and V, which total content decreases toward the weld joint, and/or an increasing total content of elements which increase the toughness and/or yield strength, such as for example Ni and Mn, which total content increases toward the weld joint.

Abstract: A rotor (10) for a thermal machine, in particular a steam or gas turbine, includes a plurality of rotor disks (12, 13, 14) which are arranged one behind the other in the rotor axis (11) and are welded to one another, at least one first rotor disk (13), which is arranged in a section of the rotor (10) which is subject to particularly high thermal loads, including a nickel-base alloy which is able to withstand high temperatures and is welded to at least one second, adjacent rotor disk (12, 14), which includes a steel which is able to withstand high temperatures.

Abstract: A thermally loaded component (10), in particular a rotor for a steam or gas turbine, includes a plurality of component sections which, during operation, are exposed to different temperature levels, a first component section being designed for temperatures of >750° C., a second component section being designed for temperatures of approximately between 750° C. and 600° C., and a third component section being designed for temperatures of <600° C.