Superplasticity of 6016 aluminum alloy at elevated temperatures

The high-temperature plastic deformation be- haviors of 6016 aluminum alloy were investigated with the temperatures ranging from 420 to 540 ℃ and the strain rates ranging from 0.001 to 1.000 s-1. The results show that 6016 aluminum alloys possess superplasticity at 500 ℃ with the strain rates ranging from 0.001 to 0.010 s-1. The grain boundary sliding （GBS） is the main mechanism of superplastic deformation of 6016 aluminum alloy. In addition, a great number of O-type cavities, almost no V type, occur in the microstructure of superplastic deformed 6016 aluminum alloy. The dislocations gather near the grain boundaries to coordinate GBS deformation. The second-phase particles effectively prevent the growth of the recrystallized grains or plastic deformation grains and pin the moving dislocations during deformation.