Stress-induced giant magneto-impedance effect of amorphous CoFeNiSiPB ribbon with magnetic field annealing

The development of high-performance magnetic field-sensitive materials is in urgent need for magnetic sensors. In this paper, the effect of magnetic field annealing on the soft magnetic properties, thermal stability and stress induced giant magneto-impedance (GMI) effect of Co69Fe5.5Ni1Si14.5-xPxB10 (x = 0, 0.5, 1, 1.5, 2) amorphous alloys were investigated in detail. Thermal analysis shows that replacing Si with a small amount of P can increase the thermal stability of the amorphous alloys. The permeability of the samples with magnetic field annealing is about 150% higher than that of the samples with stress-relieve annealing. The stress-induced GMI (GSI) results show that when the applied tensile stress is 0 MPa, 100 MPa, and 300 MPa, the maximum GMI ratio of the 1 at. % P-doping alloy with magnetic field annealing first increases from 76.6% to 102.8% and then decreases to 82%. Under the optimized measurement conditions, the magnetic field response sensitivity xi of the Co69Fe5.5Ni1-Si13.5P1B10 ribbon reached to 35.3%/Oe, the GSI ratio reached 34.3%, which has significant improvement compared to that of the stress-relieve annealing samples. Therefore, the magnetic field annealing technique greatly improved the GSI effect of the Co-based amorphous alloys, and the results obtained show a new way to develop high-performance GSI sensor materials and can be used in the construction of stress sensors.

Automated summary

This study investigates the effect of magnetic field annealing on the soft magnetic properties, thermal stability, and stress-induced GMI effect of Co-based amorphous alloys. The results show that magnetic field annealing can greatly enhance the magnetic permeability and GSI ratio of the samples, leading to improved sensitivity.