Investigation of electroplastic effect at high deformation rates for 304SS and Ti–6Al–4V

Abstract Past research has investigated an electroplastic effect for metals, i.e., decreased flow stress and increased elongation, caused by an applied electrical current aiding dislocation motion. There could be a connection between such electrically-assisted forming (EAF) processes and electromagnetic forming (EMF), where induced eddy currents are generated in the workpiece. To investigate this, Kolsky bar experiments with controlled, electrical DC current applied were conducted. Validated temperature values were calculated to assure that variations in resistive heating were determined. The results for current densities up to 180 A/mm2 show that at these high deformation rates, an electroplastic effect is not observed.

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