中文摘要：

采用外加恒电位下腐蚀电流-温度扫描方法研究了在0．5％Cl^-溶液中，SO4^2-浓度对316不锈钢点腐蚀行为的影响．结果表明，随着SO4^2-浓度的增加，钝化电流增加，开路电位降低．当SO4^2-浓度低于0．42％时，316不锈钢的临界点蚀温度比不存在SO4^2-时的临界点蚀温度低；当SO4^2-浓度大于0．42％时，临界点蚀温度比不存在SO4^2-时的临界点蚀温度高．从离子竞争吸附的角度进行分析，对SO4^2-加速与抑制点蚀两种作用规律的形成原因进行了解释．

英文摘要：

The influence of SO4^2- on the pitting corrosion behavior of 316 stainless steel has been studied by measuring the relationship of corrosion current and temperature in 0.5% Cl- solutions with different concentrations of SO4^2- at constant applied potentials. The results showed that with the increase of SO4^2- concentration, the passivation current increased and the open circuit potential decreased; When the concentration of SO4^2-was less （more） than 0.42%, the critical pitting temperature was lower （higher） than that without SO4^2-. The inhibition and acceleration effects of SO4^2- on the pitting corrosion were discussed by analyzing the mechanism of the ion-competitive adsorption.