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The influence of magnetoelastic resonance in rotation of FeSiB conventional amorphous wires under an axially applied ac field is investigated. [Copyright &y& Elsevier]

Presents a study which investigated the frequency spectrum of the rotation for magnetostrictive nickel wires as a function of the longitudinal alternating current field. Samples and experimental techniques; Results; Discussion.

In this paper we report some results on the dependence of the pulsed voltage output on the applied torsion or tensile stress in Fe/sub 77.5/Si/sub 7.5/B/sub 15/ amorphous wires used as magnetostrictive delay lines. The obtained results show a non monotonic dependence of the response of the delay line on applied torsion. For applied tensile stress the response could be fitted by a linear curve for as-cast wires and by an exponential curve for annealed wires. The good ratio between minimum and maximum magnetostrictive delay line signals and the absence of hysteresis suggest the possibility to use this technique in load cells and torque sensors. [ABSTRACT FROM PUBLISHER]

Abstract: The bi-layer thin film measurement system uses the principle of frequency modulation for the detection of displacement. The measuring system utilizes a personal computer based system using the LabVIEW® graphical programming package that provides the features necessary for acquiring the sensor signal, analyzing it and displaying the results. The results from the acquisition were compared with previously developed amplitude and phase modulation based systems to show that the frequency modulation technique provides a robust and accurate solution to evaluate magnetostrictive materials and their application in magnetic sensors. The performance of the bi-layer thin film sensor was examined and its thermal stability, over the temperature range of up to 180°C, was tested in an environmental chamber. The temperature rise does cause inductance change, but the sensor signal remains unaffected due to the nature of the frequency modulation method. Thus, having two materials, with different thermal coefficients of expansion in a bi-layer thin film sensor does not adversely influence the sensor signals. This creates a temperature independent sensor that is needed for applications where there are temperature variations. [Copyright &y& Elsevier]

Abstract: A novel method has been used for accurately measuring low-voltage signals (∼10−4 V) associated with inductance changes of bi-layer thin-film sensors under bending stress. Bi-layer sensors consist of a magnetic layer and a non-magnetic counter layer that is used to enhance the changes in the relative permeability of the material, caused by tensile or compressive stresses. The measuring system utilizes a personal computer-based system using the LabVIEW® graphical programming package. The results from the acquisition proved that this system provided a robust, cost-effective solution (as compared to hardware-based systems) to evaluate magnetostrictive materials and their application in magnetic sensors. [Copyright &y& Elsevier]

The influence of Fe addition on saturation magnetostriction at zero applied stress, λs(0), for Co72.5−xFexSi12.5B15 (x=0, 3, 4.35, 5, and 7 at%) glass-covered amorphous wires was investigated. Samples were tested in as-cast state and after AC Joule-heating under applied stress. In as-cast state the alloys with 0, 3 and 4.35 at% Fe have negative λs(0) while the alloys with 5 and 7 at% Fe have positive λs(0). [Copyright &y& Elsevier]