Preparation method of superplastic aluminum alloy plates for track traffic

A preparation method of superplastic aluminum alloy plates for track traffic relates to the manufacturing method of superplastic aluminum alloy plates. The method solves the problems of bad superplastic formability and bad mechanical properties at high temperature when the existing common aluminum alloy is prepared into plates. The method comprises the steps as follows: (1) smelting and casting alloy ingots; (2) homogenization annealing; (3) hot rolling; (4) intermediate annealing; and (5) secondary rolling the finished product thickness, and then the superplastic aluminum alloy plates for track traffic are obtained after oil scouring and finishing. The plates prepared by the method have good mechanical properties in which the tensile strength is not less than 458N/mm , the non-proportional extension strength is not less than 405N/mm and the elongation percentage after fracture is not less than 6.3%; the plates have good formability performance, the transverse elongation percentage is more than 200% and the longitudinal elongation percentage is more than 250% when the temperature is 500 DEG C; and the surface quality is good after hot forming.