Mechanical Properties and Corrosion Behavior of 5A06 Alloy in Seawater

Abstract

The mechanical properties and corrosion behavior of 5A06 alloy in a mixed solution of 0.5 mol/L H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> and seawater from Bohai Bay at 40°C for several days were investigated in this paper. The results indicate that the tensile properties of the 5A06 alloy are not very sensitive to seawater corrosion, while the fatigue life is greatly affected by it. The maximum decrements of σ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">b</sub> and σ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.2</sub> are 5.98% and 8.15%, respectively, which are due to the propagation of tensile microcracks. The maximum impairment of the fatigue life is 54.38% after corrosion for 12 days, which is related to the pitting and the combination of the galvanic effect, occluded cell effect and chemical effect. The 5A06 Al alloy mainly experiences pitting, intergranular corrosion, and exfoliation corrosion during the seawater corrosion process.