Anodic Behavior of Al–Bi and Al–Sb Alloys in 3% NaCl Solution

Abstract

The methods of polarization curves and scanning electron microscopy are used to study the pitting corrosion resistance of Al–Bi (up to 4 wt.% Bi) and Al–Sb (up to 20 wt.% Sb) binary alloys in 3% NaCl solution. Current density indices decrease at con-centrations of the alloying element up to 0.1 wt.% and, thus, corrosion slows down. At higher concentrations of antimony and bismuth, the current density corresponding to the start of passivation process increases and active regions on potentiodynamic curves decrease. This indicates that the corrosion resistance of aluminum alloys with greater content of the other phase (Bi or Sb) decreases.