模拟混凝土孔溶液中钢筋钝化膜生长动力学及孔蚀过程的研究

用恒电位电流衰减法及激光扫描光电化学显微技术研究了在于ＰＨ＝１２．５及１３．８的模拟混凝土孔溶液中钢筋钝化化膜的生长动力学及相应的破坏过程，实验结果表明，钢筋钝化膜的生长过程存在两个主要阶段，各阶段膜厚均与生长时间存在正比对数关系，但当ｔ＜３０秒和ｔ＞３０秒时，膜的生长表出出不同的动力学特征，在钝化发生点蚀前，钝化膜的微区光电流一定的预兆，腐蚀抑制剂ＮａＮＯ２影响膜的生长过程及膜厚，能提高钢筋的抗

Growth Kinetics and Breakdown of Passive Films on REBAR Electrodes in Simulated Cement Pore Solution

The growth kinetics and breakdown of passive films on REBAR electrodes insimulated cement solution(pH=12.5 and 13.8)have been investigated using in situphotoelectrochemical methods and potential step method. The results show that there are two mainstages in the growth of the film ,with two rate functions characterized by linear relation between thefilm thickness and the direct logarithm of time. There is a sign in laser-scanning photoelectrochemicalmicroscopic image just before the passive film breaks down. The addition of inhibitor NaNO_2changesthe growth kinetics and thickness of the film ,and therefore improves the resistance of pitting corrosioninduced by chloride.