Characterisation of microstructure, mechanical properties and corrosion behaviour of an AA2219 friction stir weldment

Abstract

Hardness Electrochemical behaviour Stress corrosion cracking Slow strain rate tensile test a b s t r a c t A friction stir weldment of AA2219-T87 aluminium alloy was characterised for its microstructure, mechanical properties, corrosion resistance and stress corrosion cracking behaviour. The dissolution and coarsening of the strengthening precipitates in the weld nugget and TMAZ/HAZ regions, respectively, had resulted in the softening of these regions; nevertheless, the weld joint was found to have an efficiency of around 72%. The general corrosion behaviour of the weld nugget was superior to that of the parent. The TMAZ/HAZ regions, and the weld nugget were found to have been galvanically protected in the immersion tests. Both the parent alloy and the friction stir weldment specimens exhibited a good resistance to stress corrosion cracking in 3.5% NaCl solution as was demonstrated by slow strain rate tensile tests performed at nominal strain rates of 10 −6 s −1 and 10 −7 s −1 .

A Study on Microstructure of AA2219 Friction Stir Welded Joint

“…The maximum efficiency obtained in this study was 72 %. The current result is supported with the published work [10] which has been reported at 400 RPM and 180 mm/min. At higher rotating rate, only specimens welded at low speed were accepted in this alloy.…”

Influence of Tool Rotational Speed and Axial Load in Friction Stir Welding (Fsw) of High Strength Aluminum Alloys

“…Grains in nugget zone seem very equiaxed fine grains compared to the base metals (BM) as appear for all experiments. This dynamic recrystallization process was also reported [10]. Microstructure of stir zone composed of lamellar structure with grey and partially glum grey chains with different disparity and grain size.…”

Corrosion Behavior of Keyhole-Free Friction Stir Spot Welded Joints of Dissimilar 6082 Aluminum Alloy and DP600 Galvanized Steel in 3.5% NaCl Solution

“…The corrosion of FSW joints of aluminum alloy is mainly pitting, exfoliation corrosion and intergranular corrosion [15][16][17][18]. Srinivasan et al [19] studied the corrosion properties of FSW joints of AA2219-T87 in 3.5% NaCl and NaCl + H 2 O 2 solutions. They found that the strengthening phase was dissolved and coarsened in the process of FSW, and the corrosion performance of the joint was better than that of the parent metal.…”