Effect of electric path in electric pulse aided V-bending of Ti-6Al4V: An experimental and numerical study

Abstract

Electric pulse aided deformation (EPAD) processes are gaining importance as they have potential to deform difficult-to-form materials at lower temperatures due to electro-plastic (EP) effect. To exploit the use of electric aid in metal forming processes, tool design needs special attention to minimize the joule heating (depends on electric current path) and maximize the electro-plastic effect (if any). In the present work, a custom-designed V-bending experimental setup is fabricated in such a way that current can be passed either throughout the specimen or only through the deformation zone. Effect of electric current path on force drop and springback is studied by carrying out experiments (involves thermal plus EP effect if any) and fully coupled electro-thermo-mechanical finite element analysis (thermal effects only). Results indicate that significantly higher force drop, and springback reduction are observed when current is passed through the deformation zone compared to throughout the specimen. In addition, contribution of EP effect to springback reduction is more when current is passed through the deformation zone at the end of deformation (i.e., before punch retraction).