Magnetic properties of ferromagnetic steels under different stress by the alternating current magnetization

The alternating current magnetic characteristics of the ferromagnetic materials act a significant factor to reflect their stress states. To reveal the relationship between the stress and the magnetic properties of the ferrimagnetic steels, we deduce the relation of alternating current permeability and the detected voltage of the nine-feet probe by using the basic laws in magnetism and law of electromagnetic reaction, and then we use the nine-feet probe to design and build the electromagnetic measurement system. Next some corresponding experiments were carried out to test the induction voltage of the two kinds Q-steel samples under the different stress. The results were shown that there was a similar variation tendency of the detected voltage in the two kinds the Q-steel samples, the max different values of the detected voltage can be reach 150 mV in the Q215 sample and 280 mV in the Q275 sample, respectively. Therefore, with the help of the difference detected voltage we can check the stress state of the ferrimagnetic steels conveniently in the engineering.