Abstract: Instantaneous undeformed chip thickness is one of the key parameters in modeling of milling process. Through analyzing the tooth trajectory, accurate instantaneous undeformed chip thickness can be obtained by solving cumbersome transcendental equation. Traditional chip thickness models always simplify the tooth trajectory to get approximate results. A novel instantaneous undeformed chip thickness model is proposed. Based on real tooth trajectory of end milling cutter, compensation is made for the simplified model. The chip thickness obtained by this new model is more accurate and simpler compared with traditional models. Comparison of cutting forces under different chip thickness models and experimental data indicate that this new model can provide better cutting force prediction than prior ones.

Key words: Dynamic cutting force, End milling cutter, Instantaneous undeformed chip thickness, Real tooth trajectory