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本文作者对点蚀临界击破电位(φ_(cb))提出了严格的热力学定义,提出一个点蚀核形成过程的模型,继而推导出φ_(cb)与活性阴离子活度(α_X~-)的对数呈线性关系,确定了φ_(cb)、α_X~-,c,点蚀临界温度(T_c)之间的对应关系。然后,建立起点蚀核形成过程的动力学方程式,证明实测击破电位(φ_b)与φ_(cb)的关系为:φ_b=φ_(cb)+H,推得了不同恒定极化电位条件下点蚀诱导时间(τ)与α_X~-之间的几种函数关系,从理论上解释了许多作者的实验结果。最后,提出了实测φ_(cb)的可行方法。

A Strict thermodynamic definition of the critical pitting potential (φcb)has been proposed. A model of pitting initiation was developed and the equation of φcb=α-blnα_(X~-)was derived from the definiton and the model, α_(X~-) being the activity of the active anion. It is shown that φcb, α_(X~-),c and T_c (critical temperature) are correspondent to one another, Furthermore, the kinetics equation of pitting initiation was established and the equationof φb=φcb+H was obtained. The functional relations between induction time τ and α_(X~-) under various stationary applied potentials have been determined. The theory developed in the paper can explain many authors' experimental results, It is poossible for one to determine φcb practically.