Investigation on the Ultrasonic Tube Hydroforming in the Bulging Process Using Finite Element Method

In ultrasonic tube hydroforming, the tube is hydro formed while the ultrasonic vibration is applied to the die. Prior studies provide experimental proof that ultrasonic tube hydroforming reduces corner radius, improves lubrication and uniform thickness. Use of ultrasonic vibration can decrease friction at the tube-die interface. Few attempts have been made to analyze the wire drawing while the ultrasonic vibrations were also applied during the processes. A detailed analysis and understanding of the mechanism of improvement is not possible with conventional experimental observation because the ultrasonic vibration processing phenomenon occurs at high speed. Therefore, we attempt to understand the processing mechanism of ultrasonic tube hydroforming using the finite element method (FEM).ABAQUS was used for the FEM. Forming force and formability in tube hydroforming analyzed. From these studies, we quantitatively clarified the mechanism of improved formability characteristics, such as decreased forming load and increasing bulging diameter.