Effect of Initial Microstructure on the Hot Deformation Behavior and Microstructure Evolution of Aluminum Alloy AA2060.

The microstructure evolution and hot deformation behavior of a Li-containing aluminum alloy AA2060 with different initial microstructure (homogenized vs. pre-rolled) were studied by isothermal hot deformation. The tests were performed within a wide range of deformation temperatures of 370–490 ℃ and strain rates of 0.01–10 s⁻¹. Results show that the stress drop ratio of the pre-rolled specimen is higher than that of the homogenized one under the same deformation condition. Microstructure were analyzed on the thermal processing maps in unstable and optimum processing domain, and a higher dynamic recrystallization fraction can be observed in the pre-rolled specimen that has more substructures and smaller grains. Four types of the dynamic recrystallization were observed and the mechanism for deformation softening was discussed in this work. [ABSTRACT FROM AUTHOR]