AISI 321 Stainless Steel vs. Austempered Cast Iron
Both AISI 321 stainless steel and austempered cast iron are iron alloys. They have 71% of their average alloy composition in common. There are 26 material properties with values for both materials. Properties with values for just one material (7, in this case) are not shown.
For each property being compared, the top bar is AISI 321 stainless steel and the bottom bar is austempered cast iron.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 170 to 210 | |
| 270 to 490 |
| Elastic (Young's, Tensile) Modulus, GPa | 200 | |
| 180 |
| Elongation at Break, % | 34 to 50 | |
| 1.1 to 13 |
| Poisson's Ratio | 0.28 | |
| 0.29 |
| Shear Modulus, GPa | 77 | |
| 62 to 69 |
| Tensile Strength: Ultimate (UTS), MPa | 590 to 690 | |
| 860 to 1800 |
| Tensile Strength: Yield (Proof), MPa | 220 to 350 | |
| 560 to 1460 |
Thermal Properties
| Latent Heat of Fusion, J/g | 290 | |
| 280 |
| Melting Completion (Liquidus), °C | 1430 | |
| 1380 |
| Melting Onset (Solidus), °C | 1400 | |
| 1340 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 490 |
| Thermal Conductivity, W/m-K | 16 | |
| 42 |
| Thermal Expansion, µm/m-K | 17 | |
| 13 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 16 | |
| 2.9 |
| Density, g/cm3 | 7.8 | |
| 7.5 |
| Embodied Carbon, kg CO2/kg material | 3.2 | |
| 1.8 |
| Embodied Energy, MJ/kg | 45 | |
| 25 |
| Embodied Water, L/kg | 140 | |
| 48 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 190 to 230 | |
| 19 to 95 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 130 to 310 | |
| 880 to 3970 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 25 | |
| 25 |
| Strength to Weight: Axial, points | 21 to 25 | |
| 32 to 66 |
| Strength to Weight: Bending, points | 20 to 22 | |
| 27 to 44 |
| Thermal Diffusivity, mm2/s | 4.1 | |
| 11 |
| Thermal Shock Resistance, points | 13 to 15 | |
| 25 to 53 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 0 to 0.050 |
| Arsenic (As), % | 0 | |
| 0 to 0.020 |
| Carbon (C), % | 0 to 0.080 | |
| 3.4 to 3.8 |
| Chromium (Cr), % | 17 to 19 | |
| 0 to 0.1 |
| Copper (Cu), % | 0 | |
| 0 to 0.8 |
| Iron (Fe), % | 65.3 to 74 | |
| 89.6 to 94 |
| Magnesium (Mg), % | 0 | |
| 0 to 0.040 |
| Manganese (Mn), % | 0 to 2.0 | |
| 0.3 to 0.4 |
| Molybdenum (Mo), % | 0 | |
| 0 to 0.3 |
| Nickel (Ni), % | 9.0 to 12 | |
| 0 to 2.0 |
| Nitrogen (N), % | 0 to 0.1 | |
| 0 |
| Phosphorus (P), % | 0 to 0.045 | |
| 0 to 0.040 |
| Selenium (Se), % | 0 | |
| 0 to 0.030 |
| Silicon (Si), % | 0 to 0.75 | |
| 2.3 to 2.7 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.020 |
| Tin (Sn), % | 0 | |
| 0 to 0.020 |
| Titanium (Ti), % | 0 to 0.7 | |
| 0 |
| Vanadium (V), % | 0 | |
| 0 to 0.1 |