Effect of localized liquation on pitting corrosion behavior of Nb-stabilized austenitic stainless steels was investigated by potentio-dynamic and potentiostatic polarization tests on the welding coarse-grained heat-affected zone (CGHAZ) samples simulated using finite-element software SYSWELD and Gleeble simulator. Results indicated that localized liquation gave rise to Nb-rich liquation bands along grain boundary, inhibiting metastable pit initiation and growth, but resulted in liquation cracks that facilitated the occurrence of stable pitting. Moreover, the large scatter in pitting potential and passive current density observed in CGHAZ samples was attributed to the heterogeneities in the distribution, geometry and dimensions of liquation cracks. (c) 2018 Ihe Electrochemical Society.