Performances of the fluxgate sensor with tensile stress annealed ribbons

Abstract The usability of tensile stress-annealed Romanian Co 68.25 Fe 4.5 Si 12.25 B 15 ribbons as the sensing element in Vacquier–Foerster type sensor was studied. Using the ribbons exposed to a 1/2 h pre-annealing at 300°C followed by 1/2 h stress-annealing at 300°C with applied longitudinal tensile stress of 418 MPa, good results were obtained with regard to the offset stability and noise of the sensors. The possibility of using the sensor for measuring low frequency magnetic fields was studied using Fourier analysis. The external a.c. field generates sidebands at the even harmonics in the output signal, which increase with the amplitude of the external field. The transfer characteristics of the sensor are linear for field amplitudes up to 240 μT pp and in a frequency range from 0 to 10 kHz. The measurements demonstrate the usability of the sensor in a magnetometer for both continuous and alternating magnetic field measurements.