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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 permendur", 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.

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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.