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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


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


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.

Aluminum (Al)Al 99.35 to 100
Silicon (Si)Si 0 to 0.65
Iron (Fe)Fe 0 to 0.65
Zinc (Zn)Zn 0 to 0.1
Titanium (Ti)Ti 0 to 0.060
Manganese (Mn)Mn 0 to 0.050
Copper (Cu)Cu 0 to 0.050
Magnesium (Mg)Mg 0 to 0.050
Vanadium (V)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