550TG Silicon Steel for Motor-Generator Rotors: Fatigue Testing and Material Properties

In the present work, the magnetic pole material, 550TG silicon steel was used, which has been widely used in the motor-generator rotor because of its better magnetic conductivity (Zhang et al., 2016). And the chemical compositions and mechanical properties are given in Table 1 (Zhang et al., 2017). The geometry of conventional specimen and simulation part for 550TG are shown in Figure 1.

All the specimens were machined using a wire electric discharge machine. Before fatigue testing, the conventional specimens were grinded using emery paper having a mesh of 400#, 800#, 1200#, and 2000# in order, followed by electro-polished to produce strain-free surfaces (Zhang et al., 2017).