Turbogenerator

A turbogenerator (10) has a rotor (11) having a cylindrical rotor body (13), which at each of the two ends merges into a shaft end (14), and in a middle section has the electromagnetically active region (23) of the rotor (11), in which the rotor (11) is assembled from a plurality of rotor parts which are interconnected and arranged in series on the rotor axis (19). With such a rotor, lower losses and temperatures in the end region of the rotor, and overall a higher limit rating or a broadened output range, become possible as a result of the fact that the rotor body (13) in the active region (23) is formed of an easily magnetizable material, especially a first steel, and in that the end sections of the rotor body (13) which are located outside the active region (23) and the shaft ends (14) are formed of a material with reduced magnetizability or of a non-magnetic material, especially a second steel.