Effect of 1-pyrrolidine dithiocarbamate on the galvanic coupling resistance of intermetallics – Aluminum matrix during corrosion of AA 2024-T3 in a dilute NaCl

International audience1-pyrrolidine dithiocarbamate (PDTC) effect on galvanic coupling resistance of AA 2024-T3 alloy in0.2 g L1 NaCl was evaluated by different electrochemical/gravimetric methods and surface analysis.The results obtained from polarization curves and electrochemical quartz crystal microbalance measurementsshowed that PDTC forms an adsorbed film on the Cu-rich particles, likely through a CuI–PDTC complex.At high concentrations, PDTC significantly decreases the alloy reactivity thereby providing a markedcorrosion protection. SEM–EDX analysis showed that PDTC adsorbs preferentially on the Al–Cu–Mgparticles. Electrochemical impedance spectroscopy measurements corroborate these results and showfurthermore that PDTC addition increases the galvanic coupling resistance

Ammonium pyrrolidine dithiocarbamate adsorption on copper surface in neutral chloride media

International audienceAdsorption of ammonium pyrrolidine dithiocarbamate (PDTC) on copper surface in 0.2 and 30 g L-1 NaCl media was investigated by different electrochemical methods and surface analyses. The results from electrochemical measurements showed that PDTC adsorbs rapidly on copper surface and revealed a marked effect of mixed inhibition. Surface analyses confirm the adsorption of PDTC on copper and the formation of a Cu-PDTC complex through the S atoms of PDTC. At high concentrations PDTC prevents oxides and cuprous chloride formation. XPS results showed that PDTC bonds with cuprous species indicating the formation of Cu I-PDTC complex

Coupling of electrochemical, electrogravimetric and surface analysis techniques to study dithiocarbamate/bronze interactions in chloride media

International audienceInteraction between ammonium pyrrolidinedithiocarbamate (PDTC) and bronze in 30 g L-1 NaCl was investigated at several concentrations between 0.1 and 10 mM by means of various electrochemical and spectroscopic techniques. Electrochemical measurements revealed a fast adsorption process of PDTC on Cu and Pb and the formation of a thick insulating and protective film with a high surface coverage. At high concentrations, PDTC prevents oxides formation. Surface analyses confirm PDTC adsorption on bronze mainly via interaction between sulphur atoms and Cu sites to form Cu I-PDTC complex