Corrosion inhibition impact of Pyracantha coccinea M. Roem extracts and their use as additives in zinc electroplating: Coating morphology, electrochemical and weight loss investigations

Abstract

To prevent steel from corrosion, zinc is often the metal of choice in the electroplating process. The quality of the zinc deposits is improved using organic additives in the electroplating bath for better structural and morphological properties. For this purpose, the performance of Pyracantha coccinea phenolic extracts was experimentally investigated as new eco-friendly plating additives using a direct current (DC) supply at well-defined operating parameters. The zinc deposit quality was evaluated through brightness meter, hardness meter, adhesion test, scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS), and profilometer from one side. From the other side, the corrosion resistance of the plated substrate was evaluated by gravimetric and potentiodynamic polarization measurements. The obtained results revealed that the electrodeposition process was sensitive to the variation in both additive concentration and extract type. The addition of extracts improved the quality of the deposits by providing smooth with a marked brightness especially in the case of the addition of different concentrations from BE. Furthermore, these results exhibited that the substrates coated in the presence of extracts were more resistant against corrosion than the ones layered in their absence, especially when adding 1.2g/l of EAE, which induce a decrease in the corrosion rate and current density with values of 6.2 × 10−4 mg/cm2 h and 6.6 × 10−3 mA/cm2, respectively.