Magnetostrictive Sensors

The article deals with sensors that exploit magnetostrictive materials. The contribution has mainly a tutorial form aiming to provide a self consistent description of the issue, from a macro-scale point of view, by presenting the magnetostriction effect, along with materials that naturally show a feeble effect, or special artificial alloys or compounds, developed for the scope, able to show a giant magnetostriction, normally employed for sensing. The basic magnetostriction phenomena, observed at the macro-scale are preliminary introduced in linearity assumptions, outlining axial and twisting magnetostrictive effects, that are the basic phenomena on which the sensing principle is based. Afterwards, for each effect, the concept device is introduced and discussed, referring for specific sensing solution to the wide mess of contribution available in literature.