Abstract:

Inhibition of brass corrosion by sodium diethyldithiocarbamate (SDDTC) in 3% NaCl solution was investigated by weight-loss method, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The Weight-loss results showed that SDDTC had an inhibition efficiency up to 95% in 3% NaCl at a concentration of 120 ppm. The EIS results indicated that the Rp values of brass electrodes initially increased with the SDDTC concentration and immersion time, reached a maximum at 120ppm and 72h. After that, the Rp values decreased only slightly with further increase in SDDTC concentration and immersion time. Potentiodynamic polarization results revealed that the inhibitor had simultaneous inhibitory effects on anodic and cathodic behaviors of brass in 3% NaCl solution.

Key words: brass,sodium diethyldithiocarbamate(SDDTC),mass-loss,electrochemical impedance spectroscopy(EIS),polarization curves,inhibition efficiency