Experimental methods of inhibitors assessment

The assessment of corrosion inhibitor performance in a corrosive solution can be done using different ASTM standards methods. The first method is gravimetry where the optimum concentration of inhibitor is evaluated. The second most commonly used test is electrochemical methods that include impedance spectroscopy, electrochemical frequency modulation, polarization resistance, and potentiodynamic polarization. These aforementioned tests are used for the evaluation of corrosion inhibitor adsorption and chemistry of the electrochemical reactions that take place on the metal surface. The third method involves the analysis of adsorbed inhibitor film over the metal surface using surface morphological techniques like scanning electron microscopy, contact angle, etc. The surface morphological techniques further assist in explaining the interaction among the metal and corrosion inhibitor. In the present chapter, we have tried to explain some important techniques that are used in corrosion inhibition experiments.