Investigation of the corrosion behavior of aluminum bronze alloy in alkaline environment

Abstract

AbstractIn this study, the effect of amino‐based additives including ammonia, ethanolamine and a mixture of two additives on the pH change of condenser water and corrosion behavior of aluminum bronze alloy as a structural material of condenser were investigated. The results of polarization curves, wheel tests and inductively coupled plasma showed that by increasing the pH from 8.5 to 10.5, the corrosion rate of aluminum bronze alloy and the dissolution rate of alloying elements are increased. The effect of amino‐based additives at the same pH is similar to each other. A comparison of corrosion rates determined by polarization curves. The corrosion rates for solutions contained ammonia and ethanolamine additives at pH = 10.5, were 2.92 ⋅ 10−2 and 4.55 ⋅ 10−2 mm/y respectively. The wheel test results indicated that the corrosion rates of solutions containing different additives increased to 1.1028 mm/y and 0.4504 mm/y for solutions containing ammonia and ethanolamine, respectively. Therefore, due to similar environmental conditions in the condenser and the wheel test because of the presence perturbation and biphasic fluid, it can be concluded that at pH above 10, aluminum bronze alloy has lower corrosion rate in the cooling water containing ethanolamine than ammonia additives.