论文部分内容阅读
一、线性极化法快速测定金属的腐蚀速度评价酸洗缓蚀剂的优劣,一般采用失重法。这是一种古老经典的方法,试验结果比较准确。但是试验时间较长,特别是缓蚀剂的加入,必然是通过影响金属的溶解电化学过程,从而达到降低腐蚀速度的目的。线性极化法(又称极化阻力法)是近年来发展起来的一种快速测定金属在电解质中瞬时腐蚀速度的电化学方法。采用线性极化能快速地测定不同缓蚀剂抑制腐蚀的能力,从而达到快速筛选的目的。根据斯忒恩(Stern)—盖里(Geary)提出的线性极化方程式,当金属试佯通以外电流,在自腐电位附近极化电位不超过±10mV时,对活化极化控制的腐蚀体系,△E/△I和自腐电流i_k之间存在着如下的关系式:
A linear polarization method to quickly determine the corrosion rate of metal Evaluation of the merits of pickling corrosion inhibitor, the general method of weight loss. This is an ancient classic method, the test results more accurate. However, the test time is longer, especially the addition of corrosion inhibitor, must be through the dissolution of the electrochemical process of the metal, so as to achieve the purpose of reducing the corrosion rate. Linear polarization method (also known as polarization resistance method) is developed in recent years, a rapid determination of metal in the electrolyte transient corrosion rate electrochemical method. The use of linear polarization can quickly determine the ability of different corrosion inhibitors to inhibit corrosion, so as to achieve the purpose of rapid screening. According to the linear polarization equation proposed by Stern-Geary, when the metal test is presumed to have an external current and the polarization potential does not exceed ± 10 mV near the autocorrelation potential, the activation polarization controlled corrosion system , △ E / △ I and self-decay current i_k exists between the following relationship: