A study on the mechanical property and corrosion sensitivity of an AA5086 friction stir welded joint
The mechanical property and corrosion sensitivity of a friction stir welded (FSW) AA5086 joint have been investigated. Vickers microhardness and tensile tests showed that the TMAZ/HAZ zone had the lowest microhardness value and the tensile specimen (transverse to the weld) failed in this region. Polarization experiments conducted using samples cut from each zone indicated that the HAZ had the lowest corrosion rate in 3.15 wt.% NaCl. SEM observation of the samples, Raman spectroscopic and XRD characterization of the corrosion products, and weight loss analysis after immersion tests all showed that the corrosion severity of AA5086 decreased from 3.15% NaCl to ASTM seawater and finally to 0.5 M Na2SO4. In addition, less corrosion products were observed from HAZ as compared to the other three regions, which was in agreement with the Raman and XRD analyses.