Development of a magnetostrictive torque sensor for milling process monitoring

This paper deals with a sensor system based on the magnetostrictive effect which is installed in a tool holder Sor sensing cutting torque in order to monitor the milling process. Changes in the magnetic permeability of ferrom agnetic alloy layers formed onto a rotating shaft due to torque ape detecte d by coils as changes in impedance without contracting the rotating shaft. BS mounting the magnetostrictive sensor on a tool holder, it has become pos sible to detect cutting torque as close to the cutting point as possible. T he accuracy of the proposed sensor system is confirmed through static and d ynamic evaluation tests. In order to investigate the relationship between t ool failure and cutting torque, cutting tests were performed. As the result s, the possibility of estimating flank wear and tool fracture from cutting torque detected by the proposed sensor system is recognized.