Orthophosphoric acid solutions of sodium orthovanadate, sodium tungstate, and sodium molybdate as potential corrosion inhibitors of the Al2Cu intermetallic phase

Abstract

Orthophosphoric acid solutions of sodium orthovanadate, sodium tungstate, and sodium molybdate are tested as potential corrosion inhibitors of the Al2Cu intermetallic phase. Corrosion inhibition is observed for 0.2 M solutions of Na3VO4 and Na2WO4 by increasing the pH to > 2. When the pH is < 2, the aforementioned salts increase the corrosion rate of the intermetallic phase. A 0.2 M solution of Na3VO4 causes the precipitation of vanadium phosphate on the surface of the Al2Cu phase at pH = 1.