Nanoscratch tests showing clear ploughing behavior and stable chip formation was conducted to investigate the influence of friction coefficient on the minimum thickness of cut. A theoretical model accounting for the minimum thickness of cut is used to analyze the effects of the friction coefficient and force ratio. Results show that the minimum thickness of cut is strongly dependent on both friction coefficient and force ratio. Theoretical minimum thickness of cut can be obtained when adhesion friction plays a dominant role in the cutting process. Appropriate adjustments of processing parameters are hereby suggested to result in stable micro-machining process without ploughing, not only forming fine-thin continuous chip, but also achieving high surface quality. The role of friction coefficient on the minimum thickness of cut with δ (cutting depth/edge radius) is also discussed.