Ultrasonic Assisted Equal Channel Angular ‎Extrusion Process ‎‎(UAECAE)‎

Equal channel angular extrusion (ECAE) is one of the most powerful processes for manufacturing microstructure and nanostructure ýmaterials. This process is a kind of severe plastic deformation technique, which requires large extrusion force. In this study, the numerical and experimental investigation of extrusion ýforce in ultrasonic assisted equal channel angular extrusion process (UAECAE) is carried out. ABAQUS Software is used for 2D ýfinite element analysis of the process considering superimposed ultrasonic vibrations to the round billet work material. Experimentally, the conventional and ultrasonic assisted ECAE are performed with copper material to validate simulation results. The reduction in extrusion force is observed due to ultrasonic vibrations. In order to achieve more ýaverage force reduction, it is recommended that the ýextrusion speed decreases and (or) vibrations amplitude ýincreases. Stress and strain distributions are numerically investigated in various vibrational conditions and die angles. The best die angle to obtain optimum force ýreduction is 120º. In other die angles, vibrations ýamplitudes of 15ý μmý and higher ýis necessary. Ultrasonic vibrations lead to oscillatory stresses with reduced ýaverage value, but do not influence the amount of plastic strain ýdistribution. Achieving the beneficial products in ýECAE requires heavy special equipment, whereas using UAECAE will lead to more accessible equipment. ýFinally, some optimal process parameters such as die angle, vibrations amplitude, for the proper application of these vibrations are ýproposed.