Effects of Slight Plastic Deformation on Magnetic Properties and Giant Magnetoimpedance of FeCoCrSiB Amorphous Ribbons

Slight plastic deformation of 0 to 1% by cold rolling is proposed as a treatment which may modify the responses of magnetoimpedance (MI)
sensor with an amorphous ribbon used as a sensitive element. The dependence of the magnetic properties of melt spun Fe₃Co₆₇Cr₃Si₁₅B₁₂ amorphous ribbons and their MI responses in the initial state and after slight plastic deformation on the value of the deformation were comparatively analysed. The shape of the hysteresis loops shows a clear correlation with the value of the deformation. The variations of the total impedance, the real and the imaginary components, are measured for the current intensity of 1.5mA for the frequency of 10MHz. Slight plastic deformation affects both real and imaginary components and allows a control of the shape of the MI curves in a small field in a range usually used in biomedical applications. The roposed deformation treatments can be useful for the construction of the MI sensitive elements with a new type of the responses.