7020 aluminium flat bar

7020 T651 aluminium flat bar belongs to, 7020 aluminium alloy belongs to medium and high strength Al-Zn-Mg alloy, with high strength, good welding performance and process performance, it is the main welding structural material for aerospace vehicles, ground vehicles and equipment, and is widely used. Used in the manufacture of high-speed train bodies.


 
7020 T651 aluminium flat bar
Thickness: 10~500mm
Width: 10~500mm
Length: ≤9000mm
 
 
Annealing process for 7020 T651 aluminium flat bar
 
(1) The reduction of quenching rate makes the exfoliation corrosion resistance of 7020 aluminum alloy worse, the corrosion grade changes from EA grade to EB+ grade, and the maximum corrosion depth increases from 388 μm to 570 μm.
 
(2) With the decrease of quenching rate, the content of Zn element in the grain boundary precipitation phase of 7020 aluminum alloy sheet showed a downward trend, the content of Mg element decreased slightly, and the content of Cu element did not change much.
 
(3) The reduction of the quenching rate makes the high-angle grain boundary precipitation phase of 7020 aluminum alloy coarsen, and the precipitation-free precipitation band becomes wider. The rapid dissolution of the non-precipitation precipitation zone makes the exfoliation corrosion more likely to spread along the high-angle grain boundary, resulting in resistance to exfoliation. Corrosion performance decreased.
 
7020 T651 aluminium flat bar Chemical composition
Aluminum Al (minimum): Allowance
Silicon Si: ≤0.35
Iron Fe: ≤0.40
Copper Cu: ≤0.20
Manganese Mn: 0.05~0.50
Magnesium Mg: 1.0~1.4
Chromium Cr: 0.10~0.35
Zinc Zn: 4.0~5.0
Zirconium Zr: 0.08~0.20
Zirconium+Titanium Zr+Ti: 0.08~0.25
Titanium Ti:—
Other elements not specified: each: ≤0.05; total: ≤0.15