In this study, an optimized double loop electrochemical potentiokinetic reactivation (DL-EPR) test was applied to evaluate the degree of intergranular corrosion (IGC) susceptibility of duplex stainless steel UNS S31803. The measurement in a solution of 2 M H2SO4 + 1 M HCl at 30 degrees C with a scan rate of 1.66 mV s(-1) can successfully be used to analyze the interactions between precipitation, chromium depletion, and IGC sensitization of the UNS S31803 steel, which was aged between 30 min and 48 h at 800 degrees C. To gain an insight into the phase transition, the specimens were analyzed by scanning electron microscopy (SEM) and electron dispersive X-ray spectroscopy (EDX). The results indicated healing due to re-diffusion of Cr and Mo from the sigma phase to the gamma(2) phase. (C) 2010 Elsevier Ltd. All rights reserved.