Ductile Cast Iron vs. S21904 Stainless Steel
Both ductile cast iron and S21904 stainless steel are iron alloys. They have 64% of their average alloy composition in common. There are 30 material properties with values for both materials. Properties with values for just one material (4, in this case) are not shown.
For each property being compared, the top bar is ductile cast iron and the bottom bar is S21904 stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 160 to 310 | |
| 210 to 300 |
| Elastic (Young's, Tensile) Modulus, GPa | 170 to 180 | |
| 200 |
| Elongation at Break, % | 2.1 to 20 | |
| 17 to 51 |
| Poisson's Ratio | 0.28 to 0.31 | |
| 0.28 |
| Shear Modulus, GPa | 64 to 70 | |
| 78 |
| Shear Strength, MPa | 420 to 800 | |
| 510 to 620 |
| Tensile Strength: Ultimate (UTS), MPa | 460 to 920 | |
| 700 to 1000 |
| Tensile Strength: Yield (Proof), MPa | 310 to 670 | |
| 390 to 910 |
Thermal Properties
| Latent Heat of Fusion, J/g | 270 | |
| 290 |
| Maximum Temperature: Mechanical, °C | 290 | |
| 980 |
| Melting Completion (Liquidus), °C | 1160 | |
| 1400 |
| Melting Onset (Solidus), °C | 1120 | |
| 1350 |
| Specific Heat Capacity, J/kg-K | 490 | |
| 480 |
| Thermal Conductivity, W/m-K | 31 to 36 | |
| 14 |
| Thermal Expansion, µm/m-K | 11 | |
| 17 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.4 | |
| 2.5 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.8 to 9.4 | |
| 2.9 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 1.9 | |
| 15 |
| Density, g/cm3 | 7.1 to 7.5 | |
| 7.7 |
| Embodied Carbon, kg CO2/kg material | 1.5 | |
| 3.0 |
| Embodied Energy, MJ/kg | 21 | |
| 43 |
| Embodied Water, L/kg | 43 | |
| 160 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 17 to 80 | |
| 160 to 310 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 280 to 1330 | |
| 380 to 2070 |
| Stiffness to Weight: Axial, points | 12 to 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 to 26 | |
| 25 |
| Strength to Weight: Axial, points | 17 to 35 | |
| 25 to 36 |
| Strength to Weight: Bending, points | 18 to 29 | |
| 23 to 29 |
| Thermal Diffusivity, mm2/s | 8.9 to 10 | |
| 3.8 |
| Thermal Shock Resistance, points | 17 to 35 | |
| 15 to 21 |
Alloy Composition
| Carbon (C), % | 3.0 to 3.5 | |
| 0 to 0.040 |
| Chromium (Cr), % | 0 | |
| 19 to 21.5 |
| Iron (Fe), % | 93.7 to 95.5 | |
| 59.5 to 67.4 |
| Manganese (Mn), % | 0 | |
| 8.0 to 10 |
| Nickel (Ni), % | 0 | |
| 5.5 to 7.5 |
| Nitrogen (N), % | 0 | |
| 0.15 to 0.4 |
| Phosphorus (P), % | 0 to 0.080 | |
| 0 to 0.045 |
| Silicon (Si), % | 1.5 to 2.8 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 | |
| 0 to 0.030 |