ASTM A387 Grade 91 Class 2 vs. SAE-AISI D2 Steel
Both ASTM A387 grade 91 class 2 and SAE-AISI D2 steel are iron alloys. They have a moderately high 95% 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 ASTM A387 grade 91 class 2 and the bottom bar is SAE-AISI D2 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 20 | |
| 5.0 to 16 |
| Fatigue Strength, MPa | 330 | |
| 310 to 860 |
| Poisson's Ratio | 0.28 | |
| 0.28 |
| Shear Modulus, GPa | 75 | |
| 75 |
| Shear Strength, MPa | 420 | |
| 460 to 1160 |
| Tensile Strength: Ultimate (UTS), MPa | 670 | |
| 760 to 2000 |
| Tensile Strength: Yield (Proof), MPa | 470 | |
| 470 to 1510 |
Thermal Properties
| Latent Heat of Fusion, J/g | 270 | |
| 270 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1440 |
| Melting Onset (Solidus), °C | 1420 | |
| 1390 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 480 |
| Thermal Conductivity, W/m-K | 26 | |
| 31 |
| Thermal Expansion, µm/m-K | 13 | |
| 11 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 8.9 | |
| 4.3 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 10 | |
| 5.1 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 7.0 | |
| 8.0 |
| Density, g/cm3 | 7.8 | |
| 7.7 |
| Embodied Carbon, kg CO2/kg material | 2.6 | |
| 3.4 |
| Embodied Energy, MJ/kg | 37 | |
| 50 |
| Embodied Water, L/kg | 88 | |
| 100 |
Common Calculations
| PREN (Pitting Resistance) | 13 | |
| 15 |
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 120 | |
| 92 to 100 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 580 | |
| 570 to 5940 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 25 | |
| 25 |
| Strength to Weight: Axial, points | 24 | |
| 27 to 72 |
| Strength to Weight: Bending, points | 22 | |
| 24 to 46 |
| Thermal Diffusivity, mm2/s | 6.9 | |
| 8.3 |
| Thermal Shock Resistance, points | 19 | |
| 25 to 67 |
Alloy Composition
| Aluminum (Al), % | 0 to 0.020 | |
| 0 |
| Carbon (C), % | 0.080 to 0.12 | |
| 1.4 to 1.6 |
| Chromium (Cr), % | 8.0 to 9.5 | |
| 11 to 13 |
| Copper (Cu), % | 0 | |
| 0 to 0.25 |
| Iron (Fe), % | 87.3 to 90.3 | |
| 81.3 to 86.9 |
| Manganese (Mn), % | 0.3 to 0.6 | |
| 0 to 0.6 |
| Molybdenum (Mo), % | 0.85 to 1.1 | |
| 0.7 to 1.2 |
| Nickel (Ni), % | 0 to 0.4 | |
| 0 to 0.3 |
| Niobium (Nb), % | 0.060 to 0.1 | |
| 0 |
| Nitrogen (N), % | 0.030 to 0.070 | |
| 0 |
| Phosphorus (P), % | 0 to 0.020 | |
| 0 to 0.030 |
| Silicon (Si), % | 0.2 to 0.5 | |
| 0 to 0.6 |
| Sulfur (S), % | 0 to 0.010 | |
| 0 to 0.030 |
| Titanium (Ti), % | 0 to 0.010 | |
| 0 |
| Vanadium (V), % | 0.18 to 0.25 | |
| 0 to 1.1 |
| Zirconium (Zr), % | 0 to 0.010 | |
| 0 |