The effects of DC current on the tensile properties of metals

When fabricating parts, deformation is commonly conducted in a "warm" or "hot" state in order to reduce the total energy required to form the metal. However, there are several negative effects associated with this method of energy reduction (e.g., high tool/die adhesions, environmental reactivity, etc.) Hence, another more efficient method of reducing the total deformation energy would be very beneficial. This paper examines an alternative means of reducing the energy by applying an electrical current and also determines how the material's tensile properties are affected while the current is present. Also investigated are the influences of strain rate and cold work on the electrical effects. The stress-strain curves indicate that, when current flows through a metallic specimen, the energy required to cause deformation is greatly decreased; demonstrating that electricity provides a viable alternative to increasing the workpiece temperature. However, the effect of the electricity diminishes with increasing strain rates.