1235 (Al99.35, A91235) Aluminum
1235 aluminum is a 1000-series aluminum alloy: it is considered commercially pure, and is formulated for primary forming into wrought products. 1235 is the Aluminum Association (AA) designation for this material. In European standards, it will be given as EN AW-1235. A91235 is the UNS number. Additionally, the EN chemical designation is Al99,35.
It originally received its standard designation in 1954.
The properties of 1235 aluminum include two common variations. This page shows summary ranges across both of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare 1235 aluminum to: 1000-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
69 GPa 9.9 x 106 psi
Elongation at Break
28 to 34 %
Fatigue Strength
23 to 58 MPa 3.3 to 8.5 x 103 psi
Poisson's Ratio
0.33
Shear Modulus
26 GPa 3.7 x 106 psi
Shear Strength
52 to 56 MPa 7.6 to 8.1 x 103 psi
Tensile Strength: Ultimate (UTS)
80 to 84 MPa 12 x 103 psi
Tensile Strength: Yield (Proof)
23 to 57 MPa 3.3 to 8.3 x 103 psi
Thermal Properties
Latent Heat of Fusion
400 J/g
Maximum Temperature: Mechanical
170 °C 340 °F
Melting Completion (Liquidus)
640 °C 1190 °F
Melting Onset (Solidus)
640 °C 1190 °F
Specific Heat Capacity
900 J/kg-K 0.22 BTU/lb-°F
Thermal Conductivity
230 W/m-K 130 BTU/h-ft-°F
Thermal Expansion
23 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
60 % IACS
Electrical Conductivity: Equal Weight (Specific)
200 % IACS
Otherwise Unclassified Properties
Base Metal Price
9.5 % relative
Density
2.7 g/cm3 170 lb/ft3
Embodied Carbon
8.3 kg CO2/kg material
Embodied Energy
160 MJ/kg 67 x 103 BTU/lb
Embodied Water
1190 L/kg 140 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
17 to 25 MJ/m3
Resilience: Unit (Modulus of Resilience)
3.8 to 24 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
50 points
Strength to Weight: Axial
8.2 to 8.6 points
Strength to Weight: Bending
15 to 16 points
Thermal Diffusivity
93 mm2/s
Thermal Shock Resistance
3.6 to 3.7 points
Alloy Composition
Among wrought aluminum alloys, the composition of 1235 aluminum is notable for including vanadium (V). Vanadium is used to reduce grain size and increase recrystallization temperature.
| Al | 99.35 to 100 | |
| Si | 0 to 0.65 | |
| Fe | 0 to 0.65 | |
| Zn | 0 to 0.1 | |
| Ti | 0 to 0.060 | |
| Mn | 0 to 0.050 | |
| Cu | 0 to 0.050 | |
| Mg | 0 to 0.050 | |
| V | 0 to 0.050 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM B491: Standard Specification for Aluminum and Aluminum-Alloy Extruded Round Tubes for General-Purpose Applications
Aluminum: Properties and Physical Metallurgy, John E. Hatch (editor), 1984
Aluminum Standards and Data, Aluminum Association Inc., 2013
EN 573-3: Aluminium and aluminium alloys. Chemical composition and form of wrought products. Chemical composition and form of products