Effect of Friction Stir Welding on Microstructure of a 5024 Alloy
Influence of friction stir welding (FSW) on microstructure of an Al-4.57Mg-0.35Mn-0.2Sc-0.09Zr (wt. pct.) alloy was studied. Following parameters of FSW were used: the rotation speeds of 500, 650 and 800 rpm, the traverse speed of 75 mm/min and the tilt angle of 2.5°. Defect-free welds were obtained using all these parameters. FSW leads to the formation of fully recrystallized microstructures with average grain sizes less 2 μm and a moderate dislocation density of ~1013 m–2 in the stir zone. No evidence for abnormal grain growth was found in the heat affected zone of the weld. The nanoscale Al3(Sc,Zr) dispersoids coarsened to 21 nm but retained coherent interfaces and cube-cube orientation relationship with the matrix.
C. Sommitsch, M. Ionescu, B. Mishra, E. Kozeschnik and T. Chandra
D. Yuzbekova et al., "Effect of Friction Stir Welding on Microstructure of a 5024 Alloy", Materials Science Forum, Vol. 879, pp. 2249-2254, 2017