期刊名称：Journal of Materials and Environmental Science
印刷版ISSN：2028-2508
出版年度：2014
卷号：5
期号：2
页码：520-529
出版社：University of Mohammed Premier Oujda
摘要：Buried steels in gas transmission pipelines, are solicited by soil corrosion when the protection is missed. The corrosion behavior is estimated by means of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) with and without the corrosion inhibitors containing polyphosphates ions. Appropriate models for corrosion parameters are used to fit the experimental data and extract the parameters which characterize the corrosion process. The corrosion rates were studied in different concentrations (10-3, 10-2 , 10-1 and 5.10-1 M) of corrosion inhibitors at different near neutral pH values (5.0, 6.5 and 8.5). Results showed the bare steels sensitivity to corrosion and by increasing the temperature, the polarization resistance decreases and the corrosion speed increases as well as the densities of corrosion current ICorr. Corrosion inhibitors tests showed a variation in inhibition performance with varying concentration, temperature an d immersion time. Langmuir model have been tested to describe the adsorption behaviour of inhibitor on the steel surface for the temperature range. Some thermodynamic functions of dissolution and adsorption have been determined
