DESIGN, MANUFACTURING ULTRASONIC VIBRATORY TOOL ASSISTED HOLE TURNING

Abstract

Vibration - Assisted machining has been claimed to be superior to conventional machining. One problem that exists when using vibration assisted hole machining is that it is difficult to fix the ultrasonic vibration parts on the tool post of conventional lathes. This report presents some results of design calculations, manufacturing and verification of ultrasonic vibratory tool used in vibration assisted  hole turning, fitted with a cutting tool that facilitates the turning process. An ultrasonic vibrating jig combined with a small boring tool has been designed and tested. The structure was evaluated for electrical resonance frequency, mechanical impedance and vibration amplitude at the cutting edge. Experimental hard-boring tests have been done on 20 samples of holes with 12 mm diameter. The wokpieces were made from Cr12Mo steel with hardness of HRC 60-62. The results showed that, vibration assisted hole-turning can reducce cutting force by 20% to 30%. Surface roughness from the new technique have been also improved by 40% to 71 %, compared to traditional method. The results of this study would play an important role in development, design and manufacture of complete tools for vibration assisted machining.