Modelling of frictional chatter in metal cutting

A new model of cutting process is developed in order to simplify modelling and gain a further insight into the mechanics of frictional chatter. It is based on the well known Rayleigh oscillator generating self-excited oscillations and has been applied to the shaping/planning operation. The new approach which takes into account also the forces acting on the tool flank is compared with the one developed by Wiercigroch and Krivtsov [1]. The results obtained here are alike to a certain degree but some of them show some different trends. Nonlinear dynamic behaviour is examined by bifurcation diagrams with cutting velocity and specific cutting force coefficient as the bifurcation parameters. The effect of the the tool stiffness variation in the directions parallel and perpendicular to the workpiece has been investigated. Some practical results unveiling stabilizing effects of the friction force on the tool flank have been shown.