Preparation method of superplastic aluminum alloy plates for track traffic

Abstract

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<2>, the non-proportional extension strength is not less than 405N / mm<2> 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.

Description

technical field The invention relates to a method for manufacturing an aluminum alloy superplastic plate for rail transit. Background technique In the development of rail transit, the light weight of trains is the first choice to increase the speed of trains. It can reduce the weight, reduce the resistance during operation, and reduce energy consumption. Superplastic aluminum alloys are widely used in the forming industry of complex parts of rail transit. Using them to prepare carriages can reduce the weight of the carriages and increase the load capacity of the carriages. At present, the mechanical properties of ordinary aluminum alloys are not good after being prepared into plates, and the performance is: low tensile strength (only 400-450N / mm 2 ), low non-proportional elongation strength (only 360~405N / mm 2 ), the elongation after breaking is low (only 2-6.3%), the high-temperature formability of the plate is not good, the transverse elongation is below 200% at 500 ° C...

AI Technical Summary

Problems solved by technology

The purpose of the present invention is to solve the problems of poor high-temperature superplastic formability and poor mechanical properties of existing common aluminum alloys after they are prepared into plates, and to provide a method for manufacturing aluminum alloy superplastic plates for rail transit