Microstructural Evolution and Tensile Behavior of Stir Friction Welded Al Alloys

摘要

Tensile behavior of friction stir welded Al 6061-T651, Al 7075-T6 and Al 5083-H32 alloy plates joined with different tool rotating and welding speeds was examined in the present study. Typical microstructure of friction stir welded Al alloy consists of three zones, including dynamically recrystallized zone (DXZ), thermomechanically affected zone (TMAZ) and heat affected zone. The tensile strength decreased by approximately 15 to 20 percent for age-hardened Al 6061 and Al 7075 accompanied with a slight increase in tensile elongation. Al 5083-H32 showed an approximately 20 percent increase in tensile elongation with no notable change in tensile strength. The tensile behavior of friction stir welded Al appeared to be strongly related to not only the frictional heat and microstructural evolution but also the amount of plastic flow and clustering of coarse precipitates.