Effect of thiadiazole derivatives on the corrosion of brass in natural seawater by electrochemical techniques

The inhibiting effect of thiadiazole derivatives namely,2-amino-1,3,4-thiadiazole (atd),2-amino-5-methyl-1,3,4-thiadiazole (amtd) and 2-amino-5-methylthio-1,3,4-thiadiazole (amttd) on 65-35 brass corrosion in natural seawater was studied by potentiodynamic polarization and electrochemical impedance spectroscopy. the results obtained revealed that these compounds were found to be mixed type inhibitors. the magnitude of polarization resistance values and,consequently,the inhibition efficiencies are influenced by the molecular structure of thiadiazole derivatives. inductively coupled plasma atomic emission spectroscopic (icp-aes) analysis confirmed that dezincification was minimized to a greater extent in the presence of the inhibitors. the adsorption of inhibitors on the brass surface was characterized using fourier transform infrared spectroscopy (ftir) and scanning electron microscopy (sem). the edx spectra of the brass exposed to inhibitor-containing solutions revealed the presence of the nitrogen and sulphur atoms on the surface.