Turbine rotor useful for exhaust gas turbine comprises turbine impeller with impeller hub comprising refractory metal alloy and rotor shaft with rotor shaft end facing the impeller hub, which is made of steel, and spacer sleeve

摘要

Turbine rotor (10) comprises a turbine impeller (20) with an impeller hub (22) comprising a refractory metal alloy and a rotor shaft (40) with a rotor shaft end facing the impeller hub, which is made of steel. A spacer sleeve (30) is arranged with an outer diameter and an inner diameter concentric to a rotor rotational axis, between the rotor hub and the rotor shaft end. The spacer sleeve is connected to the turbine impeller by a soldered connection with material fit of the impeller hub; and to the rotor shaft end of the rotor shaft by a welded connection with material fit. Turbine rotor (10) comprises a turbine impeller (20) with an impeller hub (22) comprising a refractory metal alloy and a rotor shaft (40) with a rotor shaft end facing the impeller hub, which is made of steel. A spacer sleeve (30) is arranged with an outer diameter and an inner diameter concentric to a rotor rotational axis, between the rotor hub and the rotor shaft end. The spacer sleeve is connected: to the turbine impeller by a soldered connection with material fit of the impeller hub; and to the rotor shaft end of the rotor shaft by a welded connection with material fit. The spacer sleeve forms a sleeve cavity in the passageway between turbine impeller and rotor shaft, which acts as a thermal choke. Independent claims are also included for: (1) an exhaust gas turbocharger for an internal combustion engine of a motor vehicle, comprising an exhaust gas turbine, a fresh air compressor, and an interposed storage area in which a turbo rotor is rotatably mounted, where the turbo rotor comprises a turbine rotor and a compressor impeller; and (2) producing a turbine rotor, comprising providing a turbine impeller with an impeller hub, providing spacer sleeve having two end faces, applying a solder material on the hub end face or sleeve end face, and merging and centering alignment of turbine impeller and spacer sleeve to an impeller assembly such that a solder gap is formed between the hub end face and the sleeve end face, heating the rotor assembly at least in the region of the pin end face and the sleeve end face, up to a predetermined soldering temperature above the melting temperature of the solder material and holding the soldering temperature for a predetermined period, cooling of the impeller assembly and generating the solder joint between the turbine impeller and spacer sleeve, providing a rotor shaft made of steel with a rotor shaft end having a shaft end surface, clamping and aligning the impeller assembly and rotor shaft in a welding device such that the shaft end surface and sleeve end face facing away from the impeller hub are directly opposite, and producing a welded joint between the impeller assembly and rotor shaft in the opposite shaft end surface and sleeve end face.