An atomistic simulation investigation on chip related phenomena in nanometric cutting of single crystal silicon at elevated temperatures

Nanometric cutting of single crystal silicon on the different crystal orientations and at a wide range of temperatures (300 K-1500 K) was studied through molecular dynamics (MD) simulations using two sorts of interatomic potentials, an analytical bond order potential (ABOP) and a modified version of Tersoff potential, so as to explore the cutting chip characteristics and chip formation mechanisms. Smaller released thermal energy and larger values of chip ratio (ratio of the uncut chip thickness to the cut chip thickness) as well as shear plane angle were obtained when cutting was performed at higher temperatures or on the (111) crystal plane, implying an enhancement in machinability of silicon. Nonetheless, the subsurface deformation depth was observed to become deeper under the aforementioned conditions. Further analysis revealed a higher number of atoms in the chip when cutting was implemented on the (110) crystal plane, attributable to the lower position of the stagnation region which triggered less ploughing action of the tool on the silicon substrate. Regardless of temperature of the substrate the minimum chip velocity angle was found while cutting the (111) crystal plane of silicon substrate whereas the maximum chip velocity angle appeared on the (110) surface. A discrepancy between the two potential functions in predicting the chip