Anodic polarization as a possible rapid method of deciding whether a given solution is corrosive or inhibitive

Abstract

AbstractAnodic polarization curves have been obtained with twelve systems of mixed corrosive and inhibitive ions and it has been found that when the results are compared with total immersion tests, the corrosive or inhibitive nature of the solutions could be estimated from the nature of the polarization curves, with only one exception (NaNO2 + NaCl).In several cases corrosion occurred in the immersion tests when the polarization curves indicated that the solution was just inhibitive, but the borderline between corrosion and passivity is not clear cut and there are reasons for believing that with solutions in the borderline region this method has a slight bias towards passivity.The probability of corrosion increases with the size of the specimen and is affected by shape, i.e. by the presence of crevices where the inhibitor may become exhausted.When modified this method may form the basis of an accelerated test.