Analytical model of temperature field in workpiece machined surface layer in orthogonal cutting

The cutting temperature has significant effects on the machined surface integrity, including the residual stress formation, metallurgical alteration and microstructural change of the workpiece. In this study, based on an analysis of the isothermal patterns in the workpiece for orthogonal cutting derived by Komanduri and Hou's thermal model, the authors noted that the temperature variations presented by the model do not indicate the cooling process of the workpiece and therefore the results are not consistent with the actual cutting process. Thus the authors improved the thermal model by introducing the heating time at the point of interest on the workpiece. The geometries of the computed isothermal patterns show that the cooling process of the workpiece has been successfully considered in the improved model. Moreover, the temperature penetration depth derived from the computed isotherms was studied under various cutting conditions. The computed results show that temperature exponentially decreases as the depth increases, which is consistent with the results obtained using the finite element model software Advant-Edge. In addition, the temperature penetration depths were compared with those obtainect from physical vapor deposition film experiment, consistency was observed with the measured values. The improved thermal model will be of great significance for the study of the residual stress and heat affected zone on the machined surface. (C) 2015 Elsevier B.V. All rights reserved.