采用动电位极化测量技术测量了316L不锈钢在0.1 mol/L NaCl水溶液中不同电位扫描速率下的极化曲线,采用Tafel直线外推法、线性极化法和弱极化区极化曲线法测定了金属的腐蚀电流密度。试验结果表明,在该溶液中316L不锈钢动电位极化曲线中的零电流电位随着电位扫描速率的增大而逐渐负移。理论推导和试验验证表明,腐蚀电流密度与电位扫描速率的平方根呈线性关系,并且电位扫描速率对利用Tafel直线外推法、线性极化法和弱极化区极化曲线法测定的腐蚀电流密度的影响不同。
Polarization curves of 316L stainless steel in 0.1 mol/L NaCl solution were measured at different potential scanning rates.The corrosion current density was measured by three methods,including tafel line extrapolation method,linear polarization method and weak polarization method.The results showed that the corrosion potential negatively moved with the increase of scanning rate.The corrosion current density had a linear relationship with the square root of the potential scanning rate.The potential scanning rate had different influence on the test results of the three measurement methods.