Effects of Spindle Speed on Impact and Scratch in Rotary Ultrasonic Face Milling

Most of existing researches related to ultrasonic machining on material removal mechanism are focused on single-grainultrasonic scratch and undeformed chip thickness. In this study for the rotary ultrasonic face milling (RUFM), two material removal modes of single and its adjacent abrasive grain with spindle speed were investigated. The impact and scratch with high-frequency vibration has been illustrated by the kinematic of multi-grain movement. We conducted the RUFM experiment to verify the proposed material removal modes. Experimental result shows that the high-frequency impact can increase surface roughness as undeformed chip thicknessdecrease, and high-frequency scratch can reduce the surface roughness as undeformed chip thickness turns up.