In this paper, a novel transducer called MAGNETOSTRICTIVE Torsional Resonant Transducer (MTRT) is introduced. The transducer is composed of a MAGNETOSTRICTIVE horn, a stainless steel backing and housing. In this transducer a spiral magnetic field, made up of longitudinal and circumferential components, is applied to the MAGNETOSTRICTIVE horn. As a result, the MAGNETOSTRICTIVE horn oscillates torsionally according to the Wiedemann effect. The MAGNETOSTRICTIVE horn is made of "2V perrnendur", which has isotropic magnetic properties. The differential equations of the torsional vibration of the transducer are derived, and the transducer is designed for a resonant frequency of 12075 Hz. Natural frequency and mode shape of the transducer are considered theoretically, numerically, and experimentally. The effects of important parameters such as axial and circumferential magnetic fields, and torsional prestress on the torsional displacement of the MTRT are considered, and the optimum working point is determined. These are promising features for industrial applications.

This paper presents an innovative bulk MAGNETOSTRICTIVE actuator made of a 2V-Permendur alloy rod, capable of functioning across multiple deformation modes—longitudinal, torsional, and flexural. In longitudinal mode, displacement is produced by the Joule effect, where a magnetic field applied along the rod’s axis, generated by a surrounding coaxial coil, induces deformation along its length. Torsional mode activation follows the Wiedemann effect, wherein an electric current passed directly through the rod produces a circumferential magnetic field that twists the material. Additionally, flexural deformation is achieved by a special designed magnetic core that directs a magnetic field to the rod’s surface, producing bending movements along the rod’s length. The actuator operates using controlled DC magnetic fields. Experimental results demonstrated outstanding performance, with maximum displacements reaching 12 microns in longitudinal mode, 7 microns in flexural mode, and 0.15 degrees in torsional mode. Such multi-functional performance highlights the actuator’s potential in precision positioning systems, with particular suitability for advanced microscopy, optical instrumentation, and other fields requiring sub-micrometer positioning accuracy.

One of the best vibration control methods using smart actuators are semi-active approaches which are as strong as active methods and need no external energy supply such as passive ones. Compared with piezoelectric-based, MAGNETOSTRICTIVE-based control methods have higher coupling efficiency, higher Curie temperature, higher flexibility to be integrated with curved structures and no depolarization problems. Semi-active methods are well developed for piezoelectrics but MAGNETOSTRICTIVE-based approaches are not as efficient, powerful and well known as piezoelectric-based methods. The aim of this work is to propose a powerful semi-active control method using MAGNETOSTRICTIVE actuators. In this paper a new type of semi-active suppression methods using MAGNETOSTRICTIVE materials is introduced which contains an equipped vibrating structure with MAGNETOSTRICTIVE patches wound by a pick-up coil connected to an electronic switch and a capacitor. The novelty of the proposed damping method is switching on the coil current signal using mentioned switch and capacitor, which is briefly named SSDC (synchronized switch damping on capacitor). In this paper, the characteristics of the semi-active pulse-switching damping technique with MAGNETOSTRICTIVE materials are studied and numerical results show significant damping for almost all types of excitations.

In the present work, FGM shells integrated with MAGNETOSTRICTIVE layers acting as distributed sensors and actuators are modeled to control vibration attenuation of FGM shells with simply supported boundary conditions. To achieve a mechanism for actively control of the oscillation amplitude of the integrated structure, a negative velocity proportional feedback control law is implemented in the study. Theoretical formulation is based on the first order shear deformation shell theory, taking into consideration transverse shear deformation and rotary inertia effects. Material properties are assumed to be temperature-dependent and graded in the thickness direction according to different volume fraction functions. A FGM cylindrical shell made up of a mixture of ceramic and metal is considered. The MAGNETOSTRICTIVE layers are also considered to be made of Terfenol-D. The influence of vibration attenuation characteristics of MAGNETOSTRICTIVE layers, the location of these layers and control parameters on vibration suppression is investigated. 

This paper presents the analysis of vibration control of a laminated composite beam that including MAGNETOSTRICTIVE layers. The formulation of problem is presented based on the shear deformation beam theory. For vibration suppression, the velocity feedback control with constant gain distributed is considered. Navier's method is applied to analyze the solution of vibration suppression of laminated beam with the simply-supported boundary conditions. The influence of lamination schemes, modes, number of smart layers at the structure, the control gain of the magnetic field intensity and smart layer position on suppress of the vibration are discussed. In addition, the controlled motion of some special laminated composite beam is tested.

In this research, a control feedback system is used to study the free vibration response of rectangular plate made of MAGNETOSTRICTIVE material (MsM) for the first time. A new trigonometric higher order shear deformation plate theory are utilized and the results of them are compared with two theories in order to clarify their accuracy and errors. Pasternak foundation is selected to modelling of elastic medium due to considering both normal and shears modulus. Also in-plane forces are uniformly applied on MAGNETOSTRICTIVE nano-plate (MsNP) in x and y directions. Nonlocal motion equations are derived using Hamilton’s principle and solved by differential quadrature method (DQM) considering different boundary conditions. Results indicate the effect of various parameters such as aspect ratio, thickness ratio, elastic medium, compression and tension loads and small scale effect on vibration behaviour of MsNP especially the controller effect of velocity feedback gain to minimizing the frequency. These finding can be used to active noise and vibration cancellation systems in micro and nano smart structures.

This paper presents a MAGNETOSTRICTIVE in-pipe impact drive mechanism (IDM). To estimate the output performances of the IDM, a dynamics model was developed based on the MAGNETOSTRICTIVE material constitutive model and mechanical model of the IDM. Therefore, an experimental system has been built to test the motion performance of IDM. Simulation and experimental results illustrate that the proposed model can accurately predict the step-size of the IDM. The working frequency of the designed IDM is from 10 to 120 Hz, with a the step-size resolution of 740 nm. The MAGNETOSTRICTIVE IDM performs good linearity, and can be applied to precision positioning.

This paper presents the surface piezomagnetoelasticity theory for size-dependent buckling analysis of an embedded piezoelectric/MAGNETOSTRICTIVE nanobeam (PMNB). It is assumed that the subjected forces from the surrounding medium contain both normal and shear components. Therefore, the surrounded elastic foundation is modeled by Pasternak foundation. The nonlocal piezomagnetoelasticity theory is applied so as to consider the small scale effects. Based on Timoshenko beam (TB) theory and using energy method and Hamilton’s principle the motion equations are obtained. By employing an analytical method, the critical magnetic, electrical and mechanical buckling loads of the nanobeam are yielded. Results are presented graphically to show the influences of small scale parameter, surrounding elastic medium, surface layers, and external electric and magnetic potentials on the buckling behaviors of PMNBs. Results delineate the significance of surface layers and external electric and magnetic potentials on the critical buckling loads of PMNBs. It is revealed that the critical magnetic, electrical and mechanical buckling loads decrease with increasing the small scale parameter. The results of this work is hoped to be of use in micro/nano electro mechanical systems (MEMS/NEMS) especially in designing and manufacturing electromagneto elastic sensors and actuators.

In this research, the free vibration of a sandwich plate made of smart MAGNETOSTRICTIVE face sheets and polymer composite core is studied. The effective elastic properties of carbon nanotube-reinforced composite are obtained by the rule of the mixture and micromechanical approach. A feedback control system follows the magnetization effect of Terfenol-D films on the vibration characteristics of a sandwich plate. Considering velocity feedback control gain value, the dimensionless frequency of sandwich plate can be changed to desired values due to magneto-mechanical coupling in MAGNETOSTRICTIVE materials. The equations of motions are derived using Reddy’ s third-order shear deformation theory, energy method, and Hamilton’ s principle. The differential quadrature method (DQM) as a numerical method is used for calculating the vibration frequency of the sandwich plate. This numerical method presents the optimal results using weighting coefficients. The findings of this study show the effect of the vibration control system and geometrical properties of the composite sheet on vibration frequency of structures. These findings can be used in marine, aerospace, and civil industries.

In this work, the structural and magnetic properties of ingot and melt-spun Pr3Fe24.75Co2.75Ti1.5 compounds have been investigated. The structural characterization of the compounds, by X-ray powder diffraction, is evidenced for a monoclinic Nd3 (Fe, Ti) 29-type structure (A2/m space group). A 2-type FOMP have been observed in the magnetic AC susceptibility curves of the ingot and melt-spun compounds.Magnetostriction and linear thermal expansion measurements have been performed by the standard strain gauge method in magnetic fields up to 1.5 T, and temperature range of 77 to 575 K. The calculated values of the ordering temperature, the room temperature saturation magnetization for the melt-spun Pr3Fe24.75Co2.75Ti1.5 compound are several times smaller than the corresponding values obtained in ingot Pr3Fe24.75Co2.75Ti1.5 compound. The above obtained results have explained the behavior of measured values of spontaneous volume, longitudinal and transverse magnetostriction.