Electrodeposition of Anticorrosive and Antimicrobial Cu-Mn Coating on Mild Steel Using Single Bath Technique
摘要
Excellent mechanical properties and affordability are the pivotal reason for the extensive usage of mild steel (MS) in the numerous industrial sectors. But inherent susceptibility of MS to corrosion under varying environmental conditions makes the corrosion protection process a major challenge. One approach is the use of protective coatings with more noble metals or alloys, including copper-manganese alloys, that act as a passive barrier to corrosion and improve the overall durability of the material. In this study, the research focuses successfully coated Cu-Mn alloy onto MS substrates using electrodeposition in a sulfate bath containing Cu and Mn ion precursor. Field emission scanning electron microscopy (FESEM) was used to study the surface morphology and texture of the coating. Energy-dispersive x-ray spectroscopy is used to confirm the elemental composition of the coatings. In order to investigate the roughness of the coating, profilometry studies are performed. The phase structure of the alloy coating is examined via x-ray diffraction, identifying the crystalline phases formed and their crystallographic orientations. Cu intermetallic phase was formed in the Cu-Mn alloy coating exhibited excellent antimicrobial activity for Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. Potentiodynamic polarization and electrochemical impedance spectroscopy tests for evaluating the corrosion behavior are performed using a 3.5 wt.% NaCl solution to simulate marine environment. At 3.00 A/dm2, the corrosion resistance of the Cu-Mn coating is the best (4.8 × 10−2 mm/y). Antimicrobial activity of the Cu-Mn alloy coatings is assessed by using direct contact plate counting method. This superior corrosion resistance of the Cu-Mn coatings is likely due to the presence of a protective oxide layer that forms on the surface of the alloy, which inhibits the diffusion of corrosive ions. Furthermore, the Cu-Mn alloy coatings are beneficial for use in the biomedical instruments as well as automobiles.