Instantaneous tool deflection model for micro milling

Abstract

This paper investigates modeling of machining forces with shearing and plowing mechanisms and estimates instantaneous tool deflections in micro end milling. Cutting forces directly affect cutter deflection, which will influence the quality of machined surfaces. Thus, it is important to model cutting forces in order to avoid imperfections in a final manufactured part. Force analysis is also essential for modeling of mechanics and dynamics of micro end milling. The proposed force model considers plowing phenomena of micro milling process and calculates it from elastic recovery of plowed workpiece material. The force distribution on the micro end mill is calculated by a mathematical model. Tool deflections during the cutting process result in final part imperfections. Therefore, it is important to predict instantaneous tool deflections in order to manufacture accurate parts and to avoid premature tool failure. Presented deflection and force models are validated on titanium alloy Ti-6Al-4V grade 5, through micro end milling experiments for a wide range of cutting conditions using laser displacement sensors and mini dynamometer.