This paper analyzes stress-strain behavior and bearing capacity of a rotor in a self-discharging separator, diameter 500 mm, manufactured from parts that underwent a hardening cycle. Three variants of the rotor were studied having the same design but differing in body materials: austenitic steels 06X17H13M3-BД, ALIII-23-43-02 and austenitic-ferritic steel 10X26H5M, ALIII-23-24. Research results allow recommending austenitic-ferritic steel for manufacture of separator rotors, as they provide necessary margin of safety for the design.