7175 (AlZn5.5MgCu(B), 3.4334) Aluminum
7175 aluminum is a 7000-series aluminum alloy: the main alloying addition is zinc and it is formulated for primary forming into wrought products. 7175 is the Aluminum Association (AA) designation for this material. In European standards, it will be given as EN AW-7175. Additionally, the EN chemical designation is AlZn5,5MgCu(B). And the UNS number is A97175.
It originally received its standard designation in 1957.
The properties of 7175 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 7175 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
3.8 to 5.9 %
Fatigue Strength
150 to 180 MPa 22 to 26 x 103 psi
Poisson's Ratio
0.32
Shear Modulus
26 GPa 3.8 x 106 psi
Shear Strength
290 to 330 MPa 42 to 48 x 103 psi
Tensile Strength: Ultimate (UTS)
520 to 570 MPa 75 to 82 x 103 psi
Tensile Strength: Yield (Proof)
430 to 490 MPa 62 to 71 x 103 psi
Thermal Properties
Latent Heat of Fusion
380 J/g
Maximum Temperature: Mechanical
180 °C 350 °F
Melting Completion (Liquidus)
640 °C 1180 °F
Melting Onset (Solidus)
480 °C 890 °F
Specific Heat Capacity
870 J/kg-K 0.21 BTU/lb-°F
Thermal Conductivity
140 W/m-K 80 BTU/h-ft-°F
Thermal Expansion
23 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
33 % IACS
Electrical Conductivity: Equal Weight (Specific)
99 % IACS
Otherwise Unclassified Properties
Base Metal Price
10 % relative
Density
3.0 g/cm3 190 lb/ft3
Embodied Carbon
8.2 kg CO2/kg material
Embodied Energy
150 MJ/kg 63 x 103 BTU/lb
Embodied Water
1130 L/kg 130 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
18 to 29 MJ/m3
Resilience: Unit (Modulus of Resilience)
1310 to 1730 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
46 points
Strength to Weight: Axial
48 to 52 points
Strength to Weight: Bending
48 to 51 points
Thermal Diffusivity
53 mm2/s
Thermal Shock Resistance
23 to 25 points
Alloy Composition
Among wrought aluminum alloys, the composition of 7175 aluminum is notable for containing comparatively high amounts of zinc (Zn) and copper (Cu). 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. Copper is used to improve strength. This comes at the cost of a decrease in corrosion resistance and weldability.
| Al | 88 to 91.4 | |
| Zn | 5.1 to 6.1 | |
| Mg | 2.1 to 2.9 | |
| Cu | 1.2 to 2.0 | |
| Cr | 0.18 to 0.28 | |
| Fe | 0 to 0.2 | |
| Si | 0 to 0.15 | |
| Mn | 0 to 0.1 | |
| Ti | 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
ASTM B247: Standard Specification for Aluminum and Aluminum-Alloy Die Forgings, Hand Forgings, and Rolled Ring Forgings
Aluminum Standards and Data, Aluminum Association Inc., 2013
ASM Specialty Handbook: Aluminum and Aluminum Alloys, J. R. Davis (editor), 1993
EN 573-3: Aluminium and aluminium alloys. Chemical composition and form of wrought products. Chemical composition and form of products
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015