Investigation on ultrasonic cavitation erosion of wrought Al-Mg alloys

Abstract

Al-Mg deformable alloys (5XXX series) are susceptible to cavitation, intergranular and tensile-cracking corrosion. To change the shape of the secondary phases precipitated on the boundaries of theα solid solution grains that reduce the cavitation resistance, some special heat treatments were applied. Cavitation erosion tests were performed in accordance with the ASTM G32 – 2010 standard. The alloys response to each heat treatment condition was investigated by measuring the mass loss as a function of cavitation time and by analyzing the damaged surfaces using optical and scanning electron microscopy. It was pointed out that the heat treatment consisting of a solution treatment at 530 °C followed by aging at 80 °C for 48 h increases the cavitation erosion resistance due to the prevention of secondary phase precipitation as continuous strips from the oversaturated solid solution.