Microstructure evolution and recrystallization behavior of hot rolled AA6061 twin-roll casting plate with different manganese contents.

AA6061 twin roll casting plate was annealed and then the hot rolling experiment was carried. Effect of Mn content on microstructure evolution and recrystallization behavior was investigated. The results show that Mn element can significantly change the recrystallization behavior of the alloy and produce particle induced recrystallization (PSN) effect. The mechanical properties of the plate would be effectively improved with appropriate Mn content. With the increase of Mn content in cast rolling plate, the number of recrystallized grains in the alloy increases; The strength and hardness of 6061 cast rolled plate increases first and then decreases with the increase of Mn content in the alloy, and the elongation decreases gradually with the increase of Mn content. Comprehensively considered, when the Mn content is 0.46%, the mechanical properties of the plate are optimal, i.e., tensile strength 197.36 MPa, yield strength 157.89 MPa and elongation 6.23% respectively. [ABSTRACT FROM AUTHOR]