Analysis of Cutting Forces From Conventional to High-Speed Milling with Straight and Helical-Flute Tools for Flat-End Milling Incorporating the Effect of Tool Runout

Abstract

\n This paper presents a systematic study to analyze the dependence of cutting forces on tool geometry, workpiece material and cutting parameters such as spindle speed, tool engagement and cutting direction in flat-end milling with tool runout. The cutting forces are determined according to a mechanistic force model considering the trochoidal flute path to calculate the undeformed chip thickness, and average cutting force and linear regression model are applied for identifying the coefficients of the force model. A series of milling processes are conducted on AZ31 Magnesium (Mg) alloy and titanium alloy (Ti6Al4V) to analyze the instantaneous cutting force curves, amplitudes of cutting forces and peak forces over a wide range of spindle speeds from conventional to high-speed milling. It is demonstrated that the values of the cutting force coefficients are higher at conventional spindle speed and decrease with an increase in spindle speed, especially when machining Ti6Al4V alloy. For the edge force coefficients, it is observed a slight variation when using cutting tools with different helix angles. Besides, the cutting force amplitudes strongly depend upon the workpiece material. The helix angle has a significant influence on the transverse force amplitude at conventional speed. The forces obtained mechanistically are also substantiated by comparison with measurements.