The giant magnetoimpedance (GMI) and giant stress impedance (GSI) behaviors of amorphous ribbons composed of three commercially available materials (Co66Si15B14Fe4Ni1, Fe81B13Si3.5C2, and Ni40Fe40Si + B19Mo1−2) with differing saturation magnetostriction constants [Formula: see text] and Young's moduli ( E) were studied under longitudinal stress/strain. The linearity of the ribbons' GSI responses and gauge factors was measured to create a figure of merit and compare their stress/strain sensing performance for strains up to ɛ = 10 × 10−3. We observed that the Ni40Fe40Si + B19Mo1−2 ribbon displayed the best performance for low strains ( ɛ < 1 × 10−3), whereas the Co66Si15B14Fe4Ni1 ribbon displayed the best performance for higher strains ( ɛ < 10 × 10−3). We conclude that the suitability of a material for sensing strains in any given strain regime has a complex dependence on both [Formula: see text] and E, the former of which dictates both the absolute magnitude of the impedance variation materials exhibit (i.e., the dynamic range), while both [Formula: see text] and E control how their impedances vary with applied strain.

We study the influence of ribbon geometry on the giant magnetoimpedance behaviour of both low-and high-aspect ratio (length (l) /width (w) = 2 to 150) ribbons made from commercially available amorphous magnetic materials. Our results indicate that the GMI with geometry is due to the combination of edge effects (due to damage created by the ribbon cutting process) and global shape anisotropy. In highaspect ratio ribbons (length (l) /width (w) 20) we find that the GMI decreases with width, which we suggest is due to the cutting process creating induced stresses that suppresses the transverse susceptibility at the edge of the material. In lower aspect ratio ribbons (length (l) /width (w) 20), shape anisotropy results in a relatively rapid increase in GMI with increasing length. We conclude that, with suitable optimisation, high-aspect ratio ribbons prepared from commercially available materials are suitable for use as macro-scale sensors that detect small magnetic fields/strains over a large sensing area.