Electrodeposition current density induced texture and grain boundary engineering in Sn coatings for enhanced corrosion resistance

Sn coatings were electrodeposited over mild steel at different current densities (5 mA cm-2, 20 mA cm-2, 40 mA cm-2, 60 mA cm-2, and 80 mA cm-2). Corrosion resistance was highest for the Sn coating fabricated at 20 mA cm-2, and that it decreased as the current density for electrodeposition increased. Electron backscatter diffraction (EBSD) results revealed that a high fraction of low angle grain boundaries (LAGBs), a high fraction of (031)[013] twin boundaries, a preferred (100) texture, and uniform stress distribution enhanced the corrosion resistance of the 20 mA cm-2 coating while the (110) growth texture deteriorated the corrosion resistance of 80 mA cm- 2 coating.