SAE-AISI 8645 Steel vs. Grey Cast Iron
Both SAE-AISI 8645 steel and grey cast iron are iron alloys. They have a moderately high 94% of their average alloy composition in common. There are 30 material properties with values for both materials. Properties with values for just one material (2, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI 8645 steel and the bottom bar is grey cast iron.
Metric UnitsUS Customary Units
Mechanical Properties
Brinell Hardness | 180 to 200 | |
160 to 300 |
Elastic (Young's, Tensile) Modulus, GPa | 190 | |
180 |
Elongation at Break, % | 12 to 23 | |
9.6 |
Fatigue Strength, MPa | 280 to 350 | |
69 to 170 |
Poisson's Ratio | 0.29 | |
0.29 |
Shear Modulus, GPa | 73 | |
69 |
Shear Strength, MPa | 380 to 400 | |
180 to 610 |
Tensile Strength: Ultimate (UTS), MPa | 600 to 670 | |
160 to 450 |
Tensile Strength: Yield (Proof), MPa | 390 to 560 | |
98 to 290 |
Thermal Properties
Latent Heat of Fusion, J/g | 250 | |
280 |
Melting Completion (Liquidus), °C | 1460 | |
1380 |
Melting Onset (Solidus), °C | 1420 | |
1180 |
Specific Heat Capacity, J/kg-K | 470 | |
490 |
Thermal Conductivity, W/m-K | 39 | |
46 |
Thermal Expansion, µm/m-K | 13 | |
11 |
Electrical Properties
Electrical Conductivity: Equal Volume, % IACS | 7.3 | |
7.4 |
Electrical Conductivity: Equal Weight (Specific), % IACS | 8.4 | |
8.9 |
Otherwise Unclassified Properties
Base Metal Price, % relative | 2.6 | |
1.9 |
Density, g/cm3 | 7.8 | |
7.5 |
Embodied Carbon, kg CO2/kg material | 1.5 | |
1.5 |
Embodied Energy, MJ/kg | 20 | |
21 |
Embodied Water, L/kg | 50 | |
44 |
Common Calculations
Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 77 to 120 | |
13 to 37 |
Resilience: Unit (Modulus of Resilience), kJ/m3 | 420 to 840 | |
27 to 240 |
Stiffness to Weight: Axial, points | 13 | |
13 |
Stiffness to Weight: Bending, points | 24 | |
25 |
Strength to Weight: Axial, points | 21 to 24 | |
5.8 to 17 |
Strength to Weight: Bending, points | 20 to 22 | |
8.7 to 17 |
Thermal Diffusivity, mm2/s | 10 | |
13 |
Thermal Shock Resistance, points | 18 to 20 | |
6.0 to 17 |
Alloy Composition
Carbon (C), % | 0.43 to 0.48 | |
3.1 to 3.4 |
Chromium (Cr), % | 0.4 to 0.6 | |
0 |
Iron (Fe), % | 96.5 to 97.7 | |
92.1 to 93.9 |
Manganese (Mn), % | 0.75 to 1.0 | |
0.5 to 0.7 |
Molybdenum (Mo), % | 0.15 to 0.25 | |
0 |
Nickel (Ni), % | 0.4 to 0.7 | |
0 |
Phosphorus (P), % | 0 to 0.035 | |
0 to 0.9 |
Silicon (Si), % | 0.15 to 0.35 | |
2.5 to 2.8 |
Sulfur (S), % | 0 to 0.040 | |
0 to 0.15 |