Aluminum 2024-T81

Aluminum 2024-T81

Subcategory: 2000 Series Aluminum Alloy; Aluminum Alloy; Metal; Nonferrous Metal

Close Analogs:

Composition Notes:
A Zr + Ti limit of 0.20 percent maximum may be used with this alloy designation for extruded and forged products only, but only when the supplier or producer and the purchaser have mutually so agreed. Agreement may be indicated, for example, by reference to a standard, by letter, by order note, or other means which allow the Zr + Ti limit.
Aluminum content reported is calculated as remainder.
Composition information provided by the Aluminum Association and is not for design.

Key Words: Aluminium 2024-T81; UNS A92024; ISO AlCu4Mg1; NF A-U4G1 (France); DIN AlCuMg2; AA2024-T81, ASME SB211; CSA CG42 (Canada)

Component    Wt. %
Al 90.7 – 94.7
Cr Max 0.1
Cu 3.8 – 4.9
Fe Max 0.5
Component    Wt. %
Mg 1.2 – 1.8
Mn 0.3 – 0.9
Other, each Max 0.05
Other, total Max 0.15
Component    Wt. %
Si Max 0.5
Ti Max 0.15
Zn Max 0.25

Material Notes: 
Information provided by Alcoa and the references. General 2024 characteristics and uses: Good machinability and surface finish capabilities. A high strength material of adequate workability. Has largely superceded 2017 for structural applications.

Uses: Aircraft fittings, gears and shafts, bolts, clock parts, computer parts, couplings, fuse parts, hydraulic valve bodies, missile parts, munitions, nuts, pistons, rectifier parts, worm gears, fastening devices, veterinary and orthopedic equipment, structures.

Data points with the AA note have been provided by the Aluminum Association, Inc. and are NOT FOR DESIGN.

Physical Properties

Physical Properties Metric English Comments
Density 2.78 g/cc 0.1 lb/in³  AA; Typical

Mechanical Properties

Hardness, Brinell 128 128  500 kg load with 10 mm ball
Hardness, Knoop 161 161  Converted from Brinell Hardness Value
Hardness, Rockwell A 48.9 48.9  Converted from Brinell Hardness Value
Hardness, Rockwell B 79 79  Converted from Brinell Hardness Value
Hardness, Vickers 146 146  Converted from Brinell Hardness Value
Tensile Strength, Ultimate 485 MPa 70300 psi
Tensile Strength, Yield 450 MPa 65300 psi
Elongation at Break 2 % 2 %  Foil
Elongation at Break 6 % 6 %  In 5 cm; Sample 1.6 mm thick
Modulus of Elasticity 72.4 GPa 10500 ksi  Average of Tension and Compression. In Aluminum alloys, the compressive modulus is typically 2% greater than the tensile modulus
Poisson’s Ratio 0.33 0.33
Fatigue Strength 125 MPa 18100 psi  500,000,000 Cycles
Shear Modulus 28 GPa 4060 ksi
Shear Strength 295 MPa 42800 psi

Electrical Properties

Electrical Resistivity 4.49e-006 ohm-cm 4.49e-006 ohm-cm  AA; Typical at 68°F

Thermal Properties

CTE, linear 68°F 23.2 µm/m-°C 12.9 µin/in-°F  AA; Typical; Average over 68-212°F range.
CTE, linear 250°C 24.7 µm/m-°C 13.7 µin/in-°F  Average over the range 20-300ºC
Specific Heat Capacity 0.875 J/g-°C 0.209 BTU/lb-°F
Thermal Conductivity 151 W/m-K 1050 BTU-in/hr-ft²-°F  AA; Typical at 77°F
Melting Point 502 – 638 °C 935 – 1180 °F  AA; Typical range based on typical composition for wrought products 1/4 inch thickness or greater. Eutectic melting is not eliminated by homogenization.
Solidus 502 °C 935 °F  AA; Typical
Liquidus 638 °C 1180 °F  AA; Typical

Processing Properties

Annealing Temperature 413 °C 775 °F
Solution Temperature 256 °C 493 °F