Optimization of the magnetic properties of materials for fluxgate sensors

A study was made of the variation of the magnetic properties of cobalt-based alloys using different compositions of CoFeSiB and CoFeSiBCr systems, which were produced by the melt-spinning technique and some of them subjected to a stress annealing treatment. A comparative study of core geometry and supporting material was also performed in order to obtain low noise fluxgate sensor core using amorphous magnetic ribbons of these alloys. The best alloy was a stress annealed Co67.5Fe3.5Si17.4B11.6 sample, which yielded fluxgate sensors with lower noise levels than those of commercial crystalline materials