Design and Evaluation of a Magnetoelastic Tensile Force Sensor

This paper introduces the basic theory behind magnetoelastic sensors which are based on the change of magnetic properties (permeability) due to mechanical stress (Villari effect). A well-known magnetoelastic sensor, the Pressductor, is described. A simulation model of a sensor is created, described, and evaluated by computing the static transfer characteristic of RMS secondary coil voltage change due to tensile stress. A real sensor is then manufactured from a polycrystalline transformer sheet and experimentally tested by using a tensile load created by water weight. The simulation and experiment show similar behavior but are not completely identical which is most likely since some material properties were taken from literature rather than from experimental measurements, like the magnetostriction coefficient and initial magnetic susceptibility.