Electrochemical Activation of Aluminum by the Addition of Tin, in 3% NaCl

The aim of our studies was to show the effect of th e addition of tin to aluminum in a solution of sodium chloride (NaCl 3%), by weight, a s well as the influence of the alloy immersion time on its corrosion resistance. To do t his, we have used, as electrochemical techniques, potentiodynamic polarization and electr ochemical impedance spectroscopy and, as metallurgical techniques, hardness paramete rs and optical microscopy performed on the alloys made of pure aluminum (99.9 %) and pure tin (99.99%). The obtained results show that the addition of tin enha nces aluminum electrochemical activation, as well as the spontaneous formation of an oxide layer containing Al 2O3, which then protects the metal from further corrosio n. During all that process, the alloy immersion in 3% NaCl acts by promoting tin’s attack nd the alloy’s corrosion.