Study of electrically-assisted indentation for surface texturing

Electrically-Assisted manufacturing is a promising hybrid manufacturing process for improved ductility and elongation during plastic deformation of metals and decreased spring-back. Most studies have focused on the deformation of a whole material by applying electric current through the whole material, and many electrically-assisted manufacturing processes including forging, rolling, and sheet metal forming have been introduced. However, plastic deformation processes on a surface, such as indentation, embossing, and scribing, are also important for functional surface texturing and marking, among other uses. In this study, the effect of a continuous electric current on indentation in stainless steel and titanium was investigated using Vickers hardness test. The hardness was decreased by the electric current during indentation with a diamond tip. The amount of decreased hardness depended on the amplitude of the electric current and the positions of two electrodes. The electric current density passing through the surface was calculated by finite element analysis, and the hardness decrease was proportional to the electric current density.