The inhibition effect of the grape pomace extract during the early stage of steel corrosion under adsorbed thin electrolyte layers was investigated. The present study was carried out to identify the components present in the 2-propanol grape pomace extract by GC-MS analysis. Gravimetric, electrochemical impedance spectroscopy, potentiodynamic polarization, scanning electron microscopy, and FTIR techniques were used to study the corrosion inhibitive. Polarization measurements have indicated that these green inhibitors acted through mixed type inhibition. SEM studies have evidenced the formation of a protective film over metal surface while FTIR supported by molecular modelling has proved that this shielding effect was caused by aldehydes particularly 2-phenylacetaldehyde and 3,7-dimethylocta-2,6-dienal.

The corrosion of a magnesium alloy containing rare earth elements (WE43 type alloy) was studied in 0.05 and 0.5 M\ud Na2SO4 or 0.1 and 1 M NaCl solutions using electrochemical techniques: linear polarization resistance, potentiodynamic\ud polarization, impedance measurements. The electrolytes favoured anodic magnesium oxidation but the\ud presence of rare earth elements improved the tendency of magnesium to passivation. The dissolution rates in\ud chlorides were higher than in sulphates because chlorides, in contrast to sulphates, interfered with the formation and\ud maintenance of a protective layer of corrosion products which decreased the severity of the attack. The effects of\ud galvanic corrosion due to cathodic intermetallic precipitates at grain boundaries were particularly evident in\ud chloride media at long testing times

No abstract

No abstract

No abstract