ASTM A387 Grade 91 Class 2 vs. ACI-ASTM CB7Cu-2 Steel
Both ASTM A387 grade 91 class 2 and ACI-ASTM CB7Cu-2 steel are iron alloys. They have 86% 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 ACI-ASTM CB7Cu-2 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 200 | |
| 300 to 420 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 20 | |
| 5.7 to 11 |
| Fatigue Strength, MPa | 330 | |
| 420 to 590 |
| Poisson's Ratio | 0.28 | |
| 0.28 |
| Shear Modulus, GPa | 75 | |
| 75 |
| Tensile Strength: Ultimate (UTS), MPa | 670 | |
| 960 to 1350 |
| Tensile Strength: Yield (Proof), MPa | 470 | |
| 760 to 1180 |
Thermal Properties
| Latent Heat of Fusion, J/g | 270 | |
| 280 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1430 |
| Melting Onset (Solidus), °C | 1420 | |
| 1380 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 480 |
| Thermal Conductivity, W/m-K | 26 | |
| 17 |
| Thermal Expansion, µm/m-K | 13 | |
| 11 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 8.9 | |
| 2.1 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 10 | |
| 2.4 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 7.0 | |
| 13 |
| Density, g/cm3 | 7.8 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 2.6 | |
| 2.6 |
| Embodied Energy, MJ/kg | 37 | |
| 38 |
| Embodied Water, L/kg | 88 | |
| 130 |
Common Calculations
| PREN (Pitting Resistance) | 13 | |
| 15 |
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 120 | |
| 71 to 120 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 580 | |
| 1510 to 3600 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 25 | |
| 25 |
| Strength to Weight: Axial, points | 24 | |
| 34 to 48 |
| Strength to Weight: Bending, points | 22 | |
| 28 to 35 |
| Thermal Diffusivity, mm2/s | 6.9 | |
| 4.6 |
| Thermal Shock Resistance, points | 19 | |
| 32 to 45 |
Alloy Composition
| Aluminum (Al), % | 0 to 0.020 | |
| 0 |
| Carbon (C), % | 0.080 to 0.12 | |
| 0 to 0.070 |
| Chromium (Cr), % | 8.0 to 9.5 | |
| 14 to 15.5 |
| Copper (Cu), % | 0 | |
| 2.5 to 3.2 |
| Iron (Fe), % | 87.3 to 90.3 | |
| 73.6 to 79 |
| Manganese (Mn), % | 0.3 to 0.6 | |
| 0 to 0.7 |
| Molybdenum (Mo), % | 0.85 to 1.1 | |
| 0 |
| Nickel (Ni), % | 0 to 0.4 | |
| 4.5 to 5.5 |
| Niobium (Nb), % | 0.060 to 0.1 | |
| 0 to 0.35 |
| Nitrogen (N), % | 0.030 to 0.070 | |
| 0 to 0.050 |
| Phosphorus (P), % | 0 to 0.020 | |
| 0 to 0.035 |
| Silicon (Si), % | 0.2 to 0.5 | |
| 0 to 1.0 |
| 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 |
| Zirconium (Zr), % | 0 to 0.010 | |
| 0 |