Effects of Process Parameters on Tool Vibration and Force Transmissibility in High-Speed Micro-Milling Machine

High-speed micro-milling is an emerging technology used to produce micro and miniaturized products with smooth surface finish and high dimensional precision. However, tool vibration is a major problem in micro-milling as it directly affects product accuracy, surface quality, and tool life. Inappropriate selection of process parameters increases radial and axial thrust as well as force transmitted to structure during micro-machining which results in rapid tool vibration. This work focuses on the experimental investigation of process parameters (cutting speed and depth of cut) in order to reduce tool vibration due to axial and radial thrust in a newly developed (Das et al. in Int J Adv Manuf Technol, 2021) high-speed micro-milling machine and to achieve stable machine operating conditions. The tool used in this experiment is a 2-flute end mill cutter (1 mm cutter diameter), and the workpiece is a commercially pure titanium (CpTi) plate. The operation is performed at different depths of cut and varying cutting speeds keeping the chip load constant. Vibration signals are acquired and processed to obtain the vibration thrust of the tool and the force transmitted to the structure due to vibration. Additionally, statistical analysis is performed on the experimental results using ANOVA, and regression equations are developed for the response functions. Eventually, optimization of the response functions has been performed using desirability analysis. The results indicate that as the depth of cut and cutting speed increases, both axial as well as radial thrust decreases leading to lower vibration amplitude of the cutting tool and reduction in force transmitted to the machine structure.