MakeItFrom.com
Menu (ESC)

2025 Aluminum vs. SAE-AISI 8645 Steel

2025 aluminum belongs to the aluminum alloys classification, while SAE-AISI 8645 steel belongs to the iron alloys. Please note that the two materials have significantly dissimilar densities. This means that additional care is required when interpreting the data, because some material properties are based on units of mass, while others are based on units of area or volume.

For each property being compared, the top bar is 2025 aluminum and the bottom bar is SAE-AISI 8645 steel.

Metric UnitsUS Customary Units

Mechanical Properties

Brinell Hardness 110
180 to 200
Elastic (Young's, Tensile) Modulus, GPa 72
190
Elongation at Break, % 15
12 to 23
Fatigue Strength, MPa 130
280 to 350
Poisson's Ratio 0.33
0.29
Shear Modulus, GPa 27
73
Shear Strength, MPa 240
380 to 400
Tensile Strength: Ultimate (UTS), MPa 400
600 to 670
Tensile Strength: Yield (Proof), MPa 260
390 to 560

Thermal Properties

Latent Heat of Fusion, J/g 400
250
Maximum Temperature: Mechanical, °C 190
410
Melting Completion (Liquidus), °C 640
1460
Melting Onset (Solidus), °C 520
1420
Specific Heat Capacity, J/kg-K 870
470
Thermal Conductivity, W/m-K 150
39
Thermal Expansion, µm/m-K 23
13

Electrical Properties

Electrical Conductivity: Equal Volume, % IACS 40
7.3
Electrical Conductivity: Equal Weight (Specific), % IACS 120
8.4

Otherwise Unclassified Properties

Base Metal Price, % relative 10
2.6
Density, g/cm3 3.0
7.8
Embodied Carbon, kg CO2/kg material 7.9
1.5
Embodied Energy, MJ/kg 150
20
Embodied Water, L/kg 1130
50

Common Calculations

Resilience: Ultimate (Unit Rupture Work), MJ/m3 55
77 to 120
Resilience: Unit (Modulus of Resilience), kJ/m3 450
420 to 840
Stiffness to Weight: Axial, points 13
13
Stiffness to Weight: Bending, points 46
24
Strength to Weight: Axial, points 37
21 to 24
Strength to Weight: Bending, points 40
20 to 22
Thermal Diffusivity, mm2/s 58
10
Thermal Shock Resistance, points 18
18 to 20

Alloy Composition

Aluminum (Al), % 90.9 to 95.2
0
Carbon (C), % 0
0.43 to 0.48
Chromium (Cr), % 0 to 0.1
0.4 to 0.6
Copper (Cu), % 3.9 to 5.0
0
Iron (Fe), % 0 to 1.0
96.5 to 97.7
Magnesium (Mg), % 0 to 0.050
0
Manganese (Mn), % 0.4 to 1.2
0.75 to 1.0
Molybdenum (Mo), % 0
0.15 to 0.25
Nickel (Ni), % 0
0.4 to 0.7
Phosphorus (P), % 0
0 to 0.035
Silicon (Si), % 0.5 to 1.2
0.15 to 0.35
Sulfur (S), % 0
0 to 0.040
Titanium (Ti), % 0 to 0.15
0
Zinc (Zn), % 0 to 0.25
0
Residuals, % 0 to 0.15
0