Numerical Study of the Effects of Ultrasonic Vibrations on the Extrusion Process

In ultrasonic vibration cold forward extrusion, the bars are extruded while the ultrasonic vibrations are applied to the die. Few attempts have been made to analyze the wire drawing, deep drawing, upsetting and rolling processes while the ultrasonic vibrations were applied during the processes. No attempts have been made to investigate on the effects of ultrasonic vibrations on the forward extrusion process, yet. A detailed analysis and understanding of the mechanism of improvement is not possible on the basis of conventional experimental observations because ultrasonic vibration processing phenomenon occur at high speeds. Therefore, in order to advance the understanding of the mechanism of ultrasonic vibration extrusion, the finite element analysis was used. The ABAQUS explicit code was used for the FEM. The results were compared with conventional cold forward extrusion. Simulations were performed for various amplitudes, frequencies, friction factors and reductions. Extrusion force versus punch travel and stress-strain distributions in the extruded parts were analyzed. From these studies, the improved extrusion characteristics such as extrusion force and material flow stress were described.

کلیدواژه ها:

Finite Element Method (FEM) ، Conventional Extrusion ، Axial Ultrasonic Vibration Extrusion ، Critical Extrusion Speed