Study on simulation and experiment of the magnetizer in magnetic flux leakage testing

As a type of research tool, the finite element method (FEM) has been widely used in engineering designs and other fields. In this paper, the magnetic circuit character of the magnetizer was studied using the finite element method and related experiments. For a type of permanent magnet multiloop magnetizer, the magnetic field distribution of the inner and 2 mm above the surface of the ferromagnetic bar was analysed with two important sizes varying. In the experiments, the high sensitive giant magnetic resistive sensor was employed. Changing the two parameters, the length index related with magnetization effect of the magnetizer was measured. The experimental results are qualitatively in agreement with the simulation. It is considered that this method will help in the parameter optimization of the device.