Influence of varying metal-to-glass ratio on GMI effect in Co70.3Fe3.7B10Si13Cr3 amorphous glass-coated microwires

The influence of a varying metal-to-glass ratio on the GMI effect in amorphous glass-coated Co70.3Fe3.7B10Si13Cr3 microwires has been investigated. In the range of frequencies investigated (1-10 MHz), the magnitude of the GMI effect increases as the metal-to-glass ratio (h) increases from 4.11 to 9.29. The GMI curves for the h = 4.11 microwire exhibit a single-peak feature for f <= 1 MHz and a double-peak feature for f > 1 MHz, whereas a consistent double-peak feature is observed for microwires with h = 8.07, 8.72, and 9.29. The largest GMI effect is achieved for microwires with h = 9.29. The anisotropy field (H-k), determined from GMI curves, increases with h = 4.11 to h = 8.07 and decreases when It > 8.07. The calculated radial stress decreases as h increases from 4.11 to 9.29. These results provide further insights into the correlation between the GMI effect and microwire dimensions towards the GMI optimization of amorphous glass-coated magnetic microwires for sensor applications. (C) 2009 Elsevier Ltd. All rights reserved.