Measurement of thinning wall for ferromagnetic structures based on the reluctance of the magnetic circuit

The measurement of inner local thinning wall is necessary for the ferromagnetic structures. This paper proposed a novel method to estimate the reduced thickness based on the reluctance of the simplified magnetic circuit model. The simulation results agree well with the mathematical model, which means we can evaluate the reduced thickness accurately under the premise of knowing the size of the thinned section. The simple principle allows the sensor to be miniaturized. All results show that this method has great promise in practical practice.