Effects of process parameters on material side flow during hard turning

The phenomenon of material side flow represents an important aspect of machined surface quality during hard turning. In this paper, an experimental study was performed to investigate the main features of this phenomenon. The effects of process parameters including edge preparation, nose radius, feed and tool wear on material side flow were examined. Two possible mechanisms for material side flow were investigated. In the first one, the material is squeezed between the tool flank face and the machined surface when chip thickness is less than a minimum value. In the second mechanism, the plastified material in the cutting zone flows through the worn trailing edge to the side of the tool. Both of these mechanisms can exist simultaneously. The results obtained from surface examination showed a strong correlation between edge preparation and material side flow. An increase in the tool nose radius resulted in a remarkable increase of material side flow. Feed had an indirect effect on material side flow. In addition, tool wear significantly affected the existence of material side flow on the machined surface. An increase in tool wear promoted the occurrence of material side flow. (C) 1999 Elsevier Science Ltd. All rights reserved.