Modeling serrated chips formation in high speed turning of hardened steel

With the increasing applications of High speed machining, serrated chip formation is becoming a more common phenomenon in metal cutting. Serrated chips usually occur in machining of difficult to cut materials at or above a threshold speed. This threshold speed value depends on the material properties like hardness and thermal conductivity. This paper describes a two dimensional Finite element model for serrated chip formation in high speed turning of hardened steel. ABAQUS/Explicit was utilized with an updated Lagrangian method to simulate serrated chips at different cutting speeds. The results show cyclic variation in the cutting forces at high cutting speeds .Also the length of cuts in the chip increases with the cutting speed and the chip changes from serrated to discontinuous.