3105 (AlMn0.5Mg0.5, 3.0505, N31, A93105) Aluminum
3105 aluminum is a 3000-series aluminum alloy: the main alloying addition is manganese, and it is formulated for primary forming into wrought products. 3105 is the Aluminum Association (AA) designation for this material. In European standards, it will be given as EN AW-3105. N31 is the British Standard (BS) designation. A93105 is the UNS number. Additionally, the EN chemical designation is AlMn0,5Mg0,5.
It originally received its standard designation in 1960.
The properties of 3105 aluminum include twelve 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 3105 aluminum to: 3000-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
Brinell Hardness
29 to 67
Elastic (Young's, Tensile) Modulus
69 GPa 10 x 106 psi
Elongation at Break
1.1 to 20 %
Fatigue Strength
39 to 95 MPa 5.7 to 14 x 103 psi
Poisson's Ratio
0.33
Shear Modulus
26 GPa 3.8 x 106 psi
Shear Strength
77 to 140 MPa 11 to 20 x 103 psi
Tensile Strength: Ultimate (UTS)
120 to 240 MPa 17 to 35 x 103 psi
Tensile Strength: Yield (Proof)
46 to 220 MPa 6.6 to 31 x 103 psi
Thermal Properties
Latent Heat of Fusion
400 J/g
Maximum Temperature: Mechanical
180 °C 360 °F
Melting Completion (Liquidus)
660 °C 1210 °F
Melting Onset (Solidus)
640 °C 1180 °F
Specific Heat Capacity
900 J/kg-K 0.21 BTU/lb-°F
Thermal Conductivity
170 W/m-K 98 BTU/h-ft-°F
Thermal Expansion
24 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
44 % IACS
Electrical Conductivity: Equal Weight (Specific)
140 % IACS
Otherwise Unclassified Properties
Base Metal Price
9.5 % relative
Calomel Potential
-750 mV
Density
2.8 g/cm3 170 lb/ft3
Embodied Carbon
8.2 kg CO2/kg material
Embodied Energy
150 MJ/kg 66 x 103 BTU/lb
Embodied Water
1180 L/kg 140 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
2.6 to 19 MJ/m3
Resilience: Unit (Modulus of Resilience)
15 to 340 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
50 points
Strength to Weight: Axial
12 to 24 points
Strength to Weight: Bending
20 to 31 points
Thermal Diffusivity
68 mm2/s
Thermal Shock Resistance
5.2 to 11 points
Alloy Composition
Among wrought aluminum alloys, the composition of 3105 aluminum is notable for containing comparatively high amounts of manganese (Mn) and magnesium (Mg). Manganese is used to improve strength without a proportional reduction in ductility. It also improves workability by controlling the grain structure of the alloy. Magnesium promotes hardenability through both heat treatment and strain hardening mechanisms. It also increases susceptibility to intergranular corrosion.
| Al | 96 to 99.5 | |
| Mn | 0.3 to 0.8 | |
| Mg | 0.2 to 0.8 | |
| Fe | 0 to 0.7 | |
| Si | 0 to 0.6 | |
| Zn | 0 to 0.4 | |
| Cu | 0 to 0.3 | |
| Cr | 0 to 0.2 | |
| 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 B209: Standard Specification for Aluminum and Aluminum-Alloy Sheet and Plate
EN 485-2: Aluminium and aluminium alloys. Sheet, strip and plate. Mechanical properties
Aluminum Standards and Data, Aluminum Association Inc., 2013
ISO 6361-2: Wrought aluminium and aluminium alloys - Sheets, strips and plates - Part 2: Mechanical properties
EN 573-3: Aluminium and aluminium alloys. Chemical composition and form of wrought products. Chemical composition and form of products
Properties and Selection: Nonferrous Alloys and Special-Purpose Materials, ASM Handbook vol. 2, ASM International, 1993
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015