204.0 (A02040) Cast Aluminum
204.0 aluminum is an aluminum alloy formulated for casting. 204.0 is the Aluminum Association (AA) designation for this material. A02040 is the UNS number.
The properties of 204.0 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 204.0 aluminum to: ANSI/AA cast aluminums (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
Brinell Hardness
90 to 120
Elastic (Young's, Tensile) Modulus
71 GPa 10 x 106 psi
Elongation at Break
5.7 to 7.8 %
Fatigue Strength
63 to 77 MPa 9.1 to 11 x 103 psi
Poisson's Ratio
0.33
Shear Modulus
27 GPa 3.8 x 106 psi
Tensile Strength: Ultimate (UTS)
230 to 340 MPa 34 to 49 x 103 psi
Tensile Strength: Yield (Proof)
180 to 220 MPa 26 to 32 x 103 psi
Thermal Properties
Latent Heat of Fusion
390 J/g
Maximum Temperature: Mechanical
170 °C 340 °F
Melting Completion (Liquidus)
650 °C 1200 °F
Melting Onset (Solidus)
580 °C 1080 °F
Solidification (Pattern Maker's) Shrinkage
1.3 %
Specific Heat Capacity
880 J/kg-K 0.21 BTU/lb-°F
Thermal Conductivity
120 W/m-K 70 BTU/h-ft-°F
Thermal Expansion
19 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
29 to 34 % IACS
Electrical Conductivity: Equal Weight (Specific)
87 to 100 % IACS
Otherwise Unclassified Properties
Base Metal Price
11 % relative
Density
3.0 g/cm3 190 lb/ft3
Embodied Carbon
8.0 kg CO2/kg material
Embodied Energy
150 MJ/kg 65 x 103 BTU/lb
Embodied Water
1150 L/kg 140 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
12 to 23 MJ/m3
Resilience: Unit (Modulus of Resilience)
220 to 350 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
46 points
Strength to Weight: Axial
21 to 31 points
Strength to Weight: Bending
28 to 36 points
Thermal Diffusivity
46 mm2/s
Thermal Shock Resistance
12 to 18 points
Alloy Composition
Among cast aluminum alloys, the composition of 204.0 aluminum is notable for containing a comparatively high amount of copper (Cu). Copper is used to improve strength. This comes at the cost of a decrease in corrosion resistance and weldability.
| Al | 93.4 to 95.5 | |
| Cu | 4.2 to 5.0 | |
| Mg | 0.15 to 0.35 | |
| Ti | 0.15 to 0.3 | |
| Fe | 0 to 0.35 | |
| Si | 0 to 0.2 | |
| Mn | 0 to 0.1 | |
| Zn | 0 to 0.1 | |
| Ni | 0 to 0.050 | |
| Sn | 0 to 0.050 | |
| res. | 0 to 0.15 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM B618: Standard Specification for Aluminum-Alloy Investment Castings
ASTM B108: Standard Specification for Aluminum-Alloy Permanent Mold Castings
ASTM B26: Standard Specification for Aluminum-Alloy Sand Castings
Handbook of Aluminum vol. 2: Alloy Production and Materials Manufacturing, George Totten and D. Scott MacKenzie (editors), 2003
Advanced Materials in Automotive Engineering, Jason Rowe (editor), 2012
Aluminum: Properties and Physical Metallurgy, John E. Hatch (editor), 1984
Properties and Selection: Nonferrous Alloys and Special-Purpose Materials, ASM Handbook vol. 2, ASM International, 1993