Improvement of Corrosion Resistance of Aluminum – Bronze Alloys In (3.5%NaCL and 2m HCl) Solutions by Indium Additions

The aim of this work is to investigate the effect of indium alloying element (0.5, 1, 1.5 and 2 wt%) on corrosion resistance of Aluminum bronze alloy in two different solutions (3.5% NaCl and 2M HCl). 15 wt% Al was used to prepper Aluminum bronze alloy using gas furnace and steel mold. The ingot homogenized at 500 ºC for 4 hours. The microstructure observation was done using light optical microscope. OCP – Time measurement and potentiodynamic polarization accomplished in the two solutions (3.5% NaCl and 2M HCl). Indium addition moved the OCP toward the negative direction, which makes the alloy less noble, whereas indium addition improve corrosion resistance by decreasing corrosion current density, the improvement percentage range is (13.2 – 72.2 %) in NaCl solution and(45.1- 91.2%) in HCl solution, the best improvement percentage is for 2% In in both solutions.