Study on micro nosing process assisted by ultrasonic vibration

Abstract

This study used experiments to investigate the effect of ultrasonic vibration on the micro nosing process of copper cup. The billets with 1 mm diameter and length were backwards extruded to form the cups with 0.1 mm wall thickness and 1.8 mm height. The cups were then used in micro nosing processes. A forming system with the ultrasonic vibration has been developed and installed on a precision press to conduct the experiments. An optical fibre sensor and a precession load cell were equipped on the ram of the press in order to accurately measure the load and stroke of the process. Two forming conditions with and without ultrasonic vibrations of 20 kHz were considered in this study. The results show that the ultrasonic vibration can improve the materials flow which leads to an even diameter along the shrunk region of the nosed cup. Moreover, the ultrasonic vibration greatly reduces the load in the micro nosing process of the copper cup.