Study on Piezomagnetic Effect of Iron Cobalt Alloy and Force Sensor

Abstract

Based on the nonlinear piezomagnetic equation, the piezomagnetic effect of prismatic iron-cobalt alloy is analyzed by using the ANSYS finite element simulation platform. The variation of the dynamic piezomagnetic coefficient of the iron-cobalt alloy under different bias magnetic fields and different stress was studied through simulation. Referring to the working condition of the tractor force sensor and according to the principle of magnetic circuit superposition, a piezomagnetic force sensor was designed and manufactured using iron-cobalt alloy. According to the electromagnetic theory and piezomagnetic effect, the three-dimensional model and magnetic circuit mathematical model of the sensor are established, and the system simulation model of the piezomagnetic sensor was established based on the MATLAB/Simulink module. The experimental platform of the magnetostrictive force sensor was built to verify the correctness of the simulation model, and the effects of bias magnetic field and force on the output characteristics are studied. The simulation and experimental results show that the maximum piezomagnetic coefficient was 9.2 T/GPA when the bias magnetic field intensity was 14.74 kA/m. The force measuring range of the sensor is 0–120 kN, and the sensor has high sensitivity within 0–80 kN. The sensor has a simple structure, is suitable for the force measurement and control of an electro-hydraulic lifter under heavy load, and can better adapt to the harsh working environment.