Semi-active control of tool vibration in hard turning using magnetorheological fluid damper

Chatter is a limiting factor that obstructs the process stability and surface finish in the machining of hard steels. Chatter control has been an active area of research for more than a century; new machine tools and cutting tools have been developed keeping chatter in mind; however, machining with existing conventional machine tools requires some adaptive techniques to combat chatter. In this article, a compact mono-tube magnetorheological damper is developed and implemented with real-time control to suppress chatter vibration. The experimental modal analysis of the cutting tool with the developed MR damper demonstrates improved damping and dynamic stiffness. A cutting tool model linked with the damper model is simulated in the Simulink workspace with ON/OFF control. The controller simulations demonstrate its timely activation of the control signal in response to vibration feedback. The experimental validation is carried out by machining AISI 01 and AISI D2 steel workpieces, commonly used in manufacturing dies and tools. Machining tests under various cutting conditions demonstrated that real-time control of the magnetorheological fluid damper could significantly improve surface finish and tool life compared to constant current.