Aluminum alloy corrosion and precipitation in high-temperature flow loop simulating environment after loss-of-coolant accidents

Abstract The aluminum (Al) alloy corrosion and precipitation tests were carried out in a high-temperature flow loop under different hypothesized post-LOCA chemistry conditions. The effect of the temperature, pH, flow rate and presence of other potential ions on Al corrosion was studied. The Al hydroxide phase transition from less-stable forms to thermodynamically stable forms during isothermal stage preferentially occurred in NaTB-buffered solution. The presence of Zn in solution could effectively inhibit Al release. The solution pH has a strong influence on Al corrosion and the volume of formed precipitate. A kinetic equation was developed to describe Al loss as a function of mass transfer coefficient and solution pH, the effect of OH- concentration on Al corrosion was more pronounced than the rate of mass transfer.