As a central component of electric motors, rotor shafts ensure the torque transfer from electrical energy to kinetic energy. Without the rotor shaft, an electric vehicle would not move. Withstanding very high loads requires highstrength and sophisticated components. Non-destructive eddy current testing is suitable for detecting material and microstructural defects before they make it into a vehicle. For example, cracks or hardness defects are detected at an early stage and defective components can be sorted out accordingly.

The MAGNATEST D testing instrument with encircling coils adapted to the test areas is used for microstructure testing of the rotor shafts. Low-frequency eddy currents are induced in the material. The different microstructural and hardness states as well as alloy constituents change the receiver currents and thus allow conclusions to be drawn about the material properties of the test part. In this way, critical areas of the rotor shaft can be quickly checked after induction hardening and the components sorted accordingly.

Fig. 2: MAGNATEST D & encircling coil

Fig. 3: STATOGRAPH CM+

Fig. 4: Typical eddy current signal in case of crack