Comparative study of open-core fluxgate magnetometric sensors made of Vacoperm 100 and C 1 and C 2 magnetic amorphous materials

Abstract

We compare the functional parameters of TFS-2 fluxgate sensors with cores of Vacoperm 100 and two Romanian amorphous magnetic materials. From the viewpoint of the offset and magnetic noise, the Co 65Fe 6Cr 7B 14Si 8 amorphous material is comparable with the polycrystalline magnetic material Vacoperm 100. In the −35 to +60°C temperature interval and for excitation currents of 200–500 mA peak values, the offset temperature drift of the sensors obtained with these two materials remains constant (0.08 and 0.15 nT/°C, respectively). These sensors have constant low magnetic noise levels. The sensors with Fe 80B 15Si 5 material cores have random offset variations and a three times greater magnetic noise level over the same temperature interval. The residual imbalance signals of the Vacoperm 100 and Co 65Fe 6Cr 7B 14Si 8 core sensors show good stability with temperature variations, whereas the Fe 80B 15Si 5 core sensors show irreversible changes between −20 and +50°C.