High-frequency magnetic energy loss based on J-A model for gallium iron alloy rod under variable stress conditions

Abstract

Magnetostrictive rods have stress-sensitive properties. They are the core component of high-frequency high-power magnetostrictive sensor and actuator devices. In practical high frequency applications, a certain compressive stress needs to be applied to improve the magnetostrictive coefficient of the material. However, unsuitable operating conditions can lead to increased magnetic energy losses and deterioration of device performance. Therefore, the loss modelling as well as other physical behaviour of the material need to be investigated before designing magnetostrictive devices. This paper builds a test platform for high frequency magnetic properties of magnetostrictive materials. The high frequency magnetic properties of rod gallium iron alloy were measured and analyzed under different exciting conditions (different compressive stress σ, magnetic field frequency f, and magnetic field strength H). Then, based on the experimental data and the classical static J-A model, a high-frequency dynamic model for rod gallium iron alloy taking into account compressive stress was developed. The novelty of the model is that the variation pattern of the J-A model parameters with frequency and compressive stress is obtained by importing the experimental data into a parameter identification program written based on a hybrid particle swarm algorithm. The trend is fitted as a polynomial function of frequency and compressive stress to account for its effect on the magnetic properties of the material. The model can effectively predict the change of high frequency magnetic loss of materials under variable compressive stress conditions. Comparing the calculated values of magnetic energy loss with the measured ones show that the maximum error is 4.37% and the average error is 2.57%, which verifies the accuracy and feasibility of the model.