Residual Stresses and Surface Roughness in Turning

The fatigue resistance of components is greatly influenced by their surface integrity. In particular, residual stresses and surface roughness are held to be the primary factors influencing fatigue resistance. This paper presents an experimental study of the influence of turning parameters on surface roughness and residual stresses. Two steels were machined by turning, the results of variations in four process parameters were measured and analyzed. These results show that in the typical range of industrial machining conditions both surface finish and residual stresses are influenced mainly by the feed rate and the nose radius; the cutting velocity and the primary rake angle play a minor, negligible role. Moreover, two empirical models were identified that can be used to predict residual stresses and roughness as a function of the two major turning parameters. These models can be used to optimize the turning conditions of components when their functionality requires the control of residual stresses and surface roughness.