2024 aluminum alloy is a kind of high-strength hard aluminum, which can be strengthened by heat treatment. It has medium plasticity in the quenched and just-quenched state. It has good spot welding and has a tendency to form intergranular cracks when it is welded by gas. The alloy is hardened after quenching and cold work. Its machinability is still good, but its machinability is low after annealing: its corrosion resistance is not high, and anodic oxidation treatment and painting methods are often used to improve its corrosion resistance.
2024 aluminum alloy is mainly used to make various high-load parts and components (but not including stamping forgings), such as skeleton parts, skins, bulkheads, ribs, spars, rivets and other working parts below 150 °C on aircraft.
[chemical composition] of 2024 aluminum alloy
Copper Cu: 3.8%-4.9%
Manganese Mn: 0.30%-1.0%
Magnesium Mg: 1.2%-1.8%
Chromium Cr: 0.10%
Silicon Si: 0.50%
Zinc Zn: 0.25%
Aluminum Al: balance
[mechanical properties] of 2024 aluminum alloy
Mechanical properties: Tensile strength σb (MPa) ≥390
Conditional yield strength σ0.2 (MPa) ≥245