Effect of tempering on mechanical proprieties and corrosion behavior of X70 HSLA steel weldments

摘要

The aim of this work is to study the effect of tempering on the corrosion behavior of X70 HSLA (high-strength low alloy) steel weldments in aerated 1Msulfuric acid solution. Two different temperatures, 450 degrees C and 650 degrees C, were selected to investigate the tempering effect on samples used in this study. Through the results obtained from microstructural characterization, tensile tests, microhardness tests, and potentiodynamic tests, it was observed that the mechanical properties were optimal after tempering. Additionally, the polarization resistance increased after tempering by reduction of factors that induce corrosion, such as residual stress. Electrochemical impedance spectroscopy was also performed to clear the mechanism and kinetics of corrosion.