Molecular dynamic study of combined effects of diamond tool rake angle and d<SUB align="right">uncut/R<SUB align="right">edge ratio on nanomachining behaviour of monocrystalline optical silicon

Abstract

Molecular dynamics (MD) of silicon ductility under contact loading due to the influence of edge radius, rake angle and undeformed (uncut) chip thickness to edge radius ratio was studied. The study showed that the stress state of silicon increased with increase in rake angle and decrease in undeformed chip thickness to edge radius ratio. Larger rake angle tool experienced stronger cutting resistance from the workpiece than the smaller rake angle, causing the specific cutting energy (SCE), cutting and thrust forces to increase. There was high kinetic friction at high undeformed chip thickness to edge radius ratio, reducing as the rake angle increases due to increase in thrust forces. The excessive negative effective rake angle at low undeformed chip thickness to edge radius ratio and high rake angle seems to be responsible for increase in phase change at the cutting region, decrease in chip length and thickness, increase in subsurface deformation.