Effect of Joule heating on GMI and magnetic properties of Fe-rich glass-coated microwires

Influence of Joule heating on magnetic properties and GMI effect of Fe75B9Si12C4 glass-coated microwires was studied. A decrease in coercivity after Joule heating is observed, while hysteresis loops of Joule heated samples maintain a rectangular shape. However, a remarkable increase in GMI ratio is observed in Joule heated samples. Observed GMI ratio improvement has been discussed considering magnetic anisotropy induced by Oersted magnetic field during Joule heating and internal stress relaxation. A remarkable GMI effect improvement observed in Joule heated Fe-rich microwires, along the fact that Fe is a more common, less expensive metal than Co, makes them suitable for magnetic sensor applications.