The frequency response of magnetoelastic sensors to stress andatmospheric pressure

摘要

Earlier work demonstrated that the characteristic resonant frequencyof magnetoelastic thick-film sensors shifts linearly downwards in response toincreasing atmospheric pressure. In this paper, the response mechanism isdetailed and shown to be a function of both pressure and the way that thesensor is mechanically stressed. Stressing the sensor, in either the elasticor plastic regime, induces out-of-plane vibrations that act as apressure-dependent damping force to the longitudinal sensor oscillationsexcited by the interrogation field. This damping force, in turn, acts to shiftthe resonant frequency of the magnetoelastic sensor lower in response toincreasing pressure.