Corrosion and optimum corrosion protection potential of friction stir welded 5083-O Al alloy for leisure ship

Electrochemical tests were undertaken to determine the optimum conditions in seawater for corrosion protection of friction stir-welded 5083-O Al alloy. Polarization trend observations show that the limiting potential that avoids the effects of hydrogen embrittlement is −1.6 V, corresponding to the crossover point between concentration polarization and activation polarization. However, the optimum protection potential is between −1.5 and −0.7 V since the current density at these values is low in the potentiostatic tests. When a galvanic cell is formed in the seawater, the welds exhibit electrochemically stable trends. Welded parts in galvanic tests with various area ratios are stable and have excellent anticorrosion characteristics.