Evaluation of Friction Characteristics Between Tool and Workpiece Using Cutting Resistance During Feed Deceleration in Interrupted Cutting—Analysis of the Definition of Calculated Friction Characteristic Values—

This study investigated the resistance forces acting during the feed deceleration of an interrupted cutting process, aiming to develop a methodology for characterizing the friction among the cutting tool, cutting fluid, and different workpiece materials. The cutting forces were analyzed to calculate the normal and tangential forces under three conditions: constant feed cutting, deceleration, and zero-cutting state. Resistance forces persisted despite the absence of active cutting. The behavior of zero-cutting forces depended on the workpiece material. A method was proposed to estimate ploughing forces, assuming a direct relationship with the frictional properties of the tool flank face. In addition, a procedure was developed to characterize the friction on the tool rake face by analyzing the relationship between normal and tangential forces obtained experimentally. By identifying inflection points in the – F n relationship, the frictional components acting on the tool rake face could be decomposed. Furthermore, the influence of the uncut chip thickness on the stability of the cutting resistance was evaluated. The results revealed a direct correlation between normal forces and frictional characteristics under the zero-cutting conditions. Finally, the study assessed the impact of different cutting fluids (dry, water-soluble oil, and vegetable oil) on frictional behavior, exhibiting significant changes in the interaction between the workpiece, cutting fluid, and tool.