SAE-AISI 8640 Steel vs. Austempered Cast Iron
Both SAE-AISI 8640 steel and austempered cast iron are iron alloys. They have a moderately high 94% of their average alloy composition in common. There are 26 material properties with values for both materials. Properties with values for just one material (5, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI 8640 steel and the bottom bar is austempered cast iron.
Metric UnitsUS Customary Units
Mechanical Properties
Brinell Hardness | 170 | |
270 to 490 |
Elastic (Young's, Tensile) Modulus, GPa | 190 | |
180 |
Elongation at Break, % | 23 | |
1.1 to 13 |
Poisson's Ratio | 0.29 | |
0.29 |
Shear Modulus, GPa | 73 | |
62 to 69 |
Tensile Strength: Ultimate (UTS), MPa | 570 | |
860 to 1800 |
Tensile Strength: Yield (Proof), MPa | 380 | |
560 to 1460 |
Thermal Properties
Latent Heat of Fusion, J/g | 250 | |
280 |
Melting Completion (Liquidus), °C | 1460 | |
1380 |
Melting Onset (Solidus), °C | 1420 | |
1340 |
Specific Heat Capacity, J/kg-K | 470 | |
490 |
Thermal Conductivity, W/m-K | 39 | |
42 |
Thermal Expansion, µm/m-K | 13 | |
13 |
Otherwise Unclassified Properties
Base Metal Price, % relative | 2.6 | |
2.9 |
Density, g/cm3 | 7.8 | |
7.5 |
Embodied Carbon, kg CO2/kg material | 1.5 | |
1.8 |
Embodied Energy, MJ/kg | 20 | |
25 |
Embodied Water, L/kg | 50 | |
48 |
Common Calculations
Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 120 | |
19 to 95 |
Resilience: Unit (Modulus of Resilience), kJ/m3 | 380 | |
880 to 3970 |
Stiffness to Weight: Axial, points | 13 | |
13 |
Stiffness to Weight: Bending, points | 24 | |
25 |
Strength to Weight: Axial, points | 20 | |
32 to 66 |
Strength to Weight: Bending, points | 20 | |
27 to 44 |
Thermal Diffusivity, mm2/s | 10 | |
11 |
Thermal Shock Resistance, points | 17 | |
25 to 53 |
Alloy Composition
Aluminum (Al), % | 0 | |
0 to 0.050 |
Arsenic (As), % | 0 | |
0 to 0.020 |
Carbon (C), % | 0.38 to 0.43 | |
3.4 to 3.8 |
Chromium (Cr), % | 0.4 to 0.6 | |
0 to 0.1 |
Copper (Cu), % | 0 | |
0 to 0.8 |
Iron (Fe), % | 96.6 to 97.8 | |
89.6 to 94 |
Magnesium (Mg), % | 0 | |
0 to 0.040 |
Manganese (Mn), % | 0.75 to 1.0 | |
0.3 to 0.4 |
Molybdenum (Mo), % | 0.15 to 0.25 | |
0 to 0.3 |
Nickel (Ni), % | 0.4 to 0.7 | |
0 to 2.0 |
Phosphorus (P), % | 0 to 0.035 | |
0 to 0.040 |
Selenium (Se), % | 0 | |
0 to 0.030 |
Silicon (Si), % | 0.15 to 0.35 | |
2.3 to 2.7 |
Sulfur (S), % | 0 to 0.040 | |
0 to 0.020 |
Tin (Sn), % | 0 | |
0 to 0.020 |
Vanadium (V), % | 0 | |
0 to 0.1 |