Investigations on the Effect of Ultrasonic Vibration in Cylindrical Cup Drawing Processes

Abstract

This paper presents experimental and numerical investigations on the effect of ultrasonic vibration on cylindrical cup drawing processes of a cold rolled steel sheet (SPCC). An experimental apparatus to superimpose high frequency oscillation on deep drawing processes was constructed by installing ultrasonic vibration generators consist of piezoelectric transducer and resonator to the die. Conventional and vibration-assisted cylindrical deep drawing tests were carried out for various drawing ratios, and the limiting drawing ratio (LDR) was compared. In order to evaluate the contribution of ultrasonic vibration to the reduction of friction between tools and a material quantitatively, finite element analyses were carried out. Through a series of parametric analyses, friction coefficients which minimize the differences of punch load histories between the experiment and simulation were determined. The results showed that the application of ultrasonic vibration make for improving LDR by reducing the friction between tools and the material, effectively.