Finite Element and Experimental Analysis of an Axisymmetric Electromechanical Converter with a Magnetostrictive Rod

Abstract

The paper presents the numerical and experimental investigations of the axisymmetric magnetostrictive actuator with a Terfenol-D rod. The applied model consists of equations that describe the magnetic and mechanical displacement fields. The equations of both fields are coupled through a nonlinear magneto-mechanical constitutive law. The model is considered as 2D axisymmetric. The finite element method is used to solve the field equations. Special attention is paid to the proper definition of magneto-mechanical relations. These relations are formed from measurements. A unique test stand is designed for the experimental investigation. The selected results of the simulation are compared with the measurement results. The comparison shows that the applied numerical model is sufficiently accurate.

New Type of Linear Magnetostrictive Motor Designed for Outer Space Applications, from Concept to End-Product

“…The central active subassembly (A), consisting of the active magnetostrictive core (1), is made of Terfenol-D (Tb 0.3 Dy 0.7 Fe 1.9-1.95 ), with a deformation capacity of 1200 ppm, a relative magnetic permeability of µ r = 10, and a coupling factor of 0.75. It acts on the pusher rod (2). Two cylindrical permanent magnets (3,4) contribute to the bias magnetic field.…”

“…Moreover, axial compression (mechanical bias) may be used to enhance the magnetostrictive strain of the Terfenol-D rod; hence, the GMM is usually pre-stressed with a spring. Of these two (magnetization and pre-stress), the proposed model in [2] accounts for the mechanical bias only. GMAs are generally used in applications where several requirements must be met simultaneously, such as high forces (hundreds of N), small linear displacements (tens of µm), and high frequencies (of up to 15 kHz).…”

Magneto-Mechanical Coupling Analysis of Automobile Brake by Wire System Based on Giant-Magnetostrictive Actuator

“…Nevertheless, the actual magnetic flux was not experimentally verified in this study, and the actual magnetic field strength could not be obtained. Finite element analysis and experimental studies on giant-magnetostrictive motor converters have been carried out by Stachowiak et al They coupled and carried out an experimental study of the displacement and mechanical fields through nonlinear magnetomechanical intrinsic law and the simulation results are in general agreement with the experimental results [12]. However, this research only verified the typical structure of GMA and did not optimize its structural design.…”

Nonlinear Dynamics Study of Giant Magnetostrictive Actuators with Fractional Damping

“…The giant magnetostrictive actuator (GMA) made from GMM rods as the core component has the advantages of a high magneto-mechanical coupling coefficient, good low frequency response, high magnetostrictive coefficient, and a high output force and wide vibration response band. It has been widely used in the fields of micro-displacement drive, sensor, precision positioning control and vibration control [2][3][4][5][6][7]. However, due to the influence of multiple coupled nonlinear factors during the operation of the GMA system [8,9], the nonlinearity of GMA structural materials, i.e., the stress-strain relationship does not satisfy Hooke's law, and the nonlinearity of the system's construction, is reflected in the nonlinearity of deformation and external forces, and the recovery force and damping are nonlinear functions of structural vibration displacement and velocity, respectively.…”