7204 Aluminum
7204 aluminum is a 7000-series aluminum alloy: the main alloying addition is zinc and it is formulated for primary forming into wrought products. 7204 is the Aluminum Association (AA) designation for this material. In European standards, it will be given as EN AW-7204. Additionally, the UNS number is A97204.
It received its standard designation in 2005, making it a fairly young material.
The properties of 7204 aluminum include three common variations. This page shows summary ranges across all of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare 7204 aluminum to: 7000-series alloys (top), all aluminum alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Elastic (Young's, Tensile) Modulus
70 GPa 10 x 106 psi
Elongation at Break
11 to 13 %
Fatigue Strength
110 to 130 MPa 16 to 19 x 103 psi
Poisson's Ratio
0.33
Shear Modulus
26 GPa 3.8 x 106 psi
Shear Strength
130 to 220 MPa 19 to 33 x 103 psi
Tensile Strength: Ultimate (UTS)
220 to 380 MPa 31 to 54 x 103 psi
Tensile Strength: Yield (Proof)
120 to 310 MPa 18 to 45 x 103 psi
Thermal Properties
Latent Heat of Fusion
380 J/g
Maximum Temperature: Mechanical
210 °C 400 °F
Melting Completion (Liquidus)
640 °C 1180 °F
Melting Onset (Solidus)
520 °C 970 °F
Specific Heat Capacity
880 J/kg-K 0.21 BTU/lb-°F
Thermal Conductivity
150 W/m-K 86 BTU/h-ft-°F
Thermal Expansion
24 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
39 % IACS
Electrical Conductivity: Equal Weight (Specific)
120 % IACS
Otherwise Unclassified Properties
Base Metal Price
9.5 % relative
Density
2.9 g/cm3 180 lb/ft3
Embodied Carbon
8.4 kg CO2/kg material
Embodied Energy
150 MJ/kg 66 x 103 BTU/lb
Embodied Water
1140 L/kg 140 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
25 to 40 MJ/m3
Resilience: Unit (Modulus of Resilience)
110 to 710 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
47 points
Strength to Weight: Axial
21 to 36 points
Strength to Weight: Bending
28 to 40 points
Thermal Diffusivity
58 mm2/s
Thermal Shock Resistance
9.4 to 16 points
Alloy Composition
Among wrought aluminum alloys, the composition of 7204 aluminum is notable for including vanadium (V) and containing a comparatively high amount of zinc (Zn). Vanadium is used to reduce grain size and increase recrystallization temperature. Zinc is used to achieve significant increases in strength, at the cost of increased susceptibility to stress corrosion cracking. Among other things, this limits weldability.
| Al | 90.5 to 94.8 | |
| Zn | 4.0 to 5.0 | |
| Mg | 1.0 to 2.0 | |
| Mn | 0.2 to 0.7 | |
| Fe | 0 to 0.35 | |
| Si | 0 to 0.3 | |
| Cr | 0 to 0.3 | |
| Zr | 0 to 0.25 | |
| Ti | 0 to 0.2 | |
| Cu | 0 to 0.2 | |
| V | 0 to 0.1 | |
| res. | 0 to 0.15 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
Handbook of Aluminum Bonding Technology and Data, J. D. Minford, 1993
Aluminum: Properties and Physical Metallurgy, John E. Hatch (editor), 1984
ISO 6361-2: Wrought aluminium and aluminium alloys - Sheets, strips and plates - Part 2: Mechanical properties