Analysis of cutting forces and roughness during hard turning of bearing steel

An experimental study has been carried out to analyze the effect of cutting parameters (cutting speed, feed and depth of cut) and tool nose radius on the surface roughness and the cutting force components during hard turning of the AISI 52100 (50 HRC) steel with a ceramic cutting tool. The tests have been conducted according to the methodology of planning experiments, based on an orthogonal plan of Taguchi (L27). By using the response surface methodology (RSM), the components of the cutting force and the roughness of the machined surface were modeled and the effects of the input parameters were analyzed statistically by ANOVA and RSM. The results show that the feed (f), the tool nose radius (r), the cutting speed (Vc), the interaction between feed and tool nose radius (fxr) as well as that of the quadratic effect (f2) all have significant effects on the surface roughness (Ra). The feed is the most influencing factor with a contribution of 47.31%. The components of the cutting force were strongly influenced by the depth of cut, followed by the advance with a lower degree. By comparing the experimental values with those predicted by the models of the cutting force components and the surface roughness, it appears that they are in very good correlation.