Subject　to　Gleeble　processing,　microstructures　of　weld　heat　affected　zone　were　simulated　in　X80　steel.　Corrosion　behavior　of　the　simulated　specimen　with　a　microstructure　gradient　was　studied　by　polarization,　local　electrochemical　impedance　spectroscopy　and　scanning　vibrating　electrode　technique.　Microstructure　of　granular　bainite　mixed　with　ferrite　(region　B)　showed　the　highest　charge　transfer　resistance　and　the　most　positive　current　density　value.　Acicular　ferrite　base　metal　displayed　the　lowest　charge　transfer　resistance　and　the　most　negative　current　density.　Both　the　positive　and　negative　peak　current　densities　increased　at　the　first　few　hours　of　immersion　followed　by　a　decrease.　(C)　2014　Elsevier　Ltd.　All　rights　reserved.