The Portevin-Le Chatelier effect with surface potential

Surface potential of AA 3204 undergoing a serrated plastic flow (PLC effect) was monitored in a dilute brine electrolyte under various strain rates at 30 °C. Significant potential bursts at the launch of the stress drop regimes of the flow were revealed. The serration counts and frequency of the PLC effect matched with that of the bursts precisely, and average burst magnitude (ΔV) was found to be directly proportional with that of the stress drops (Δσ). The bursts were attributed to the electrons in strain fields of the slip steps exposed to the electrolyte during the local banding events. The utility of the electrochemical set-up for investigation of the PLC effect and monitoring deformation and damage progress of materials were affirmed.