Improved Machining Stability of Thin-Walled Aluminum Parts through Eddy Current Damping

Abstract

Higher efficiency can be achieved during machining of thin-walled parts while maintaining quality of surface finish by damping part vibrations, thereby increasing the maximum chatter-free depth of cut over a range of spindle speeds. Models exist both to characterize the effect of damping in machining and to quantify the result of incorporating eddy current damping on a simple vibrating cantilever beam. Impact testing was performed on undamped and magnetically damped cantilever beams to quantify the amount of damping introduced by the magnet configuration being used. Machining tests were carried out on thin-floored compliant parts with and without magnetic damping. The use of magnets during machining resulted in cutting forces reduced by a factor of 10 and surface Ra being reduced by a factor of 25.