Modelling of Tool Temperature in Modulation-assisted Machining

Modulation-assisted machining (MAM) superimposes a controlled, low-frequency oscillation in the feed direction of conventional machining (CM). The process transforms the otherwise continuous cutting into a series of interrupted cutting events. As a result, the tool is subject to time-varying temperature field in MAM. This paper proposes an analytical model for predicting the transient tool temperature in MAM. Chip formation during MAM is studied to investigate the time-varying undeformed chip thickness. The heat flux in MAM is determined based on a non-equal distance shear zone model. A reduction in specific energy due to modulation is also considered. Then, the tool is modeled as a semi-infinite rectangular corner, and a Green's function approach is applied for calculating the temperature. The analytical results are compared with finite element modeling (FEM). A set of cylindrical turning experiments is carried out with and without modulation, showing the discrete chip formation in MAM and related reduction in tool temperature. The analytical model provides a framework for characterizing the effect of the process parameters on applications for modulation-assisted machining.