Development of four-pole magnets for motorcycle speed sensor

The aim of this work was the development of magnets in a ring form, four poles, for speed sensor of motorcycles, from barium and strontium ferrites. The model of the magnets developed was based on magnets already manufactured for this purpose. Thus, several raw materials were tested with additive variation. The samples were prepared and measured, and the data were compared to commercially produced magnets. Finally, the magnets were mounted in the speed sensors and field tests were carried out. The magnets developed showed excellent results as having the highest remanent magnetism of 500 Gauss for the PFL barium ferrite alloy with 4% of stearic acid and 1 or 2% of silica, resulting 20% above the required magnetism.