An Experimental Study of Ultrasonic Assisted Micro-Holes Drilling

Abstract

The ultrasonic vibration has increasing implementation in metal machining as an assisted method. It adds high frequency vibration with low amplitude to the workpiece or the cutting tool and it has been verified to have the great potential on cutting force reduction, surface quality improvement, tool wear decrease and so on. This paper applied the ultrasonic vibration to the micro-holes drilling of 30CrNiMo8. In order to identify the performance of the combination, an ultrasonic machine tool with the vibration in the feed direction was designed and assembled. The spindle speed and feed rate and were taken as the controlled variables and a series of experiments were carried out. The results indicated that the ultrasonic assisted micro-holes drilling transformed the drilling process and the mechanism of the chip formation, which noticeably suppressed the exit burrs and ensured the dimensional accuracy and the surface roughness of the micro-holes.