局部腐蚀微区电化学测试技木的研究

本文研究了KCl-Ag/AgCl微参比电极、微Cl~-选择电极和钨微电极的制备与性能,初步的结果表明:微参比电极具有稳定的电位及较小的温度系数;在没有其它卤离子存在的情况下,微Cl~-电极的电位与logαci~-有良好的线性关系,溶液酸度的改变和其它离子的存在对这一线性关系影响不大;在酸性条件下,在NaCl或MgCl_2溶液中,钨微电极具有稳定的电位,这一电位与溶液pH值有良好的线性关系,而且与溶液浓度无关,当溶液中存在的其他离子浓度不高时,对上述线性关系也没有影响。将上述微电极应用于缝隙腐蚀和应力腐蚀研究,得到一些现场跟踪测量的结果,这些结果可与其他作者用其它方法所获得的结果相印证。

AN INVESTIGATION OF MICROELECTROCHEMICAL MEASUREMENT TECHNIQUE IN LOCALIZED CORROSION STUDY

The properties of KCl-Ag/AgCl reference microelectrode, chloride ion selective microelectrode and tungesten microelectrode have been investigated. Preliminary results show that reference microelectrode has a stable potential with a small coefficient of temperature. In the absence of other halide (?)ons, the potential of ehloride ion selective microelectrode bears a linear relationship with logac(?) The change in the solution acidity and the presence of other ions have less effect on the linear relationship. Under acid conditions, the tungesten mjcroelectrode in NaCl or MgCl_2 solution have a stable potential which is quite linear with the pH value of the solution and is independent of the solution concentration. Other (?)ons existing in the solution in low concentration, do not affect the linear relationship. Some results have been obtained when the microeiectrodes in crevice corrosion and stress corrosion cracking studies and agreed well with the results obtained by other methods.