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随机理论是为研究同体材料由于外加应力所产生的断裂而发展起来的一种理论。根据这种理论,研究了点蚀电位和点蚀产生的诱导时间的统计变化。为获得大量的数据,研究了一种多路点蚀试验装置。该装置可用一台恒电位仪在一次实验中测量12个试样的点蚀电位或诱导时间。对304不锈钢在3.5％NaCl溶液中所获得的试验数据进行的分析证明:恒电位下的点蚀过程包括三个互相銜接的过程,其中每一个过程都具有取决于电位和时间的不同点蚀产生速率,由电位扫描方法测定的点蚀电位只能探测第一个过程。实验证明了本理论的予测,即点蚀电位随着电位扫描速度的平方根而增加。点蚀产生的速率与电位的线性关系表明:点蚀过程并非由电化学反应所控制,而是由鈍化膜的电机械破坏所控制。
Stochastic theory is a theory developed to study the fracture of a bulk material due to the application of external stresses. According to this theory, the statistical changes of the induction time caused by pitting potential and pitting corrosion were studied. To obtain a large amount of data, a multi-channel pitting test apparatus was studied. The device can use a potentiostat in an experiment measuring the pitting potential of 12 samples or induction time. Analysis of the experimental data obtained for 304 stainless steel in 3.5% NaCl solution proves that the pitting process at constant potential includes three interconnected processes, each of which has a different pitting depending on potential and time The pitting potential, as measured by the potential sweep method, can only detect the first process. Experiments show that the theory predicts that the pitting potential increases with the square root of the potential scan rate. The linear relationship between the rate of pitting and the potential shows that the pitting process is not controlled by the electrochemical reaction but controlled by the electro-mechanical failure of the passivation film.