Effect of Tool Edge Geometry on Workpiece Subsurface Deformation and Through-Thickness Residual Stresses for Hard Turning of AISI 52100 Steel

Abstract An experimental investigation was conducted to determine the effect of tool cutting edge geometry on workpiece subsurface deformation and through-thickness residual stresses for finish hard turning of through-hardened AISI 52100 steel. Polycrystalline cubic boron nitride (PCBN) inserts with “up-sharp” edges, edge hones, and chamfers were used as the cutting tools in this study. Examination of the workpiece microstructure reveals that large edge hone tools produce substantial subsurface plastic flow. Flow is not observed when turning with small edge hone tools or chamfered tools, and the workpiece microstructure appears random for these cases. Examination of through-thickness residual stresses shows that large edge hone tools produce deeper, more compressive residual stresses than are produced by small edge hone tools or chamfered tools. Explanations for these effects are offered based on assumed contact conditions between the tool and workpiece.