摘要
93％硫酸中处于阳极钝化状态下的碳钢电极,在转入较小极化电流的恒电流状态后,会发生很有规律的正弦波形的电位振荡现象。发生电位振荡的条件是:起初的恒电位极化电位等于或正于+300毫伏(相对于同一介质中的铂参比电极);接着的恒电流极化在电流密度的一定范围内电位振荡的幅度和周期都变化不大,但如低于临界值则不发生振荡。温度升高,振幅减小,周期变短。搅拌某一时间后使振荡消失。电位振荡是由于极化电流不足以维持稳定的钝态,局部表面膜反复地溶解和形成.从而导致活化-钝化交替变换。
When a mild steel electrode in 93％ sulfuic acid was first controlled potentiostatically over 300mV(vs Pt in the same medium) and then galvanostatically at a reduced currentdensity, regular sinusoidal oscillations of potential were observed. Analysis of the experimental results indicated that the periodic phenomenon was caused by alternate active-passive transition on the electrode surface. Their amplitude and period were almost independent on the polarization potential and current. When temperature increased, the period became shorter, and the amplitude smaller. Vigorous stirring could stop the oscillations. Passiveactive alternation of weak sites of the electrode surface caused the potential oscillations.
出处
《中国腐蚀与防护学报》
CAS
CSCD
1992年第4期301-307,共7页
Journal of Chinese Society For Corrosion and Protection
基金
国家自然科学基金重大项目所属课题
中国科学院腐蚀科学开放实验室资助
