7022 aluminium alloy

(ρ)2.77 g/cm³Mechanical propertiesYoung's modulus (E)70 GPaTensile strength (σ_t)440 MPa (64 ksi)Elongation (ε) at break6%Poisson's ratio (ν)0.33Hardness—Rockwell81 HRBThermal propertiesThermal conductivity (k)165 W/m*KLinear thermal expansion coefficient (α)2.35*10⁻⁵ K⁻¹

7022 aluminium alloy is an alloy in the wrought aluminium-zinc family (7000 or 7xxx series). It is one of the more complex grades in the 7000 series, with at least 87.85% aluminium by weight.

Like most other highly alloyed alloys, 7022 is a high strength alloy, with yield strength of 370 MPa. Designed to be resistant to stress corrosion cracking, it has decent corrosion and oxidation resistance comparable to 7075 aluminium alloy^[1] but worse than 7039 aluminium alloy. Good machinability, thermal conductivity and dimensional stability make 7022 alloy a material of choice for plastic injection molds.^[2]

7022 alloy can be heat treated to increase tensile strength in expense of workability, with most common grade been T651.

Notes: Alternative names for 7022 alloy are A7022 and AA7022.

Chemical Composition

1. Aluminium: 88.35 to 92.4%
2. Zinc: 4.3 to 5.2%
3. Magnesium: 2.6 to 3.7%
4. Copper: 0.5 to 1.0%
5. Manganese: 0.1 to 0.4%
6. Chromium: 0.1 to 0.3%
7. Silicon: 0.5% max
8. Iron: 0.5% max^[3]
9. Titanium: 0.2% max
10. Zirconium: 0.2% max
11. Other: 0.15% max

See also

• Aleris (first maker of A7022)

References

Aluminum alloy table