ACI-ASTM CN7M Steel vs. ACI-ASTM CN3M Steel
Both ACI-ASTM CN7M steel and ACI-ASTM CN3M steel are iron alloys. Both are furnished in the heat treated (HT) condition. They have a moderately high 92% of their average alloy composition in common.
For each property being compared, the top bar is ACI-ASTM CN7M steel and the bottom bar is ACI-ASTM CN3M steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 140 | |
| 140 |
| Elastic (Young's, Tensile) Modulus, GPa | 200 | |
| 200 |
| Elongation at Break, % | 44 | |
| 34 |
| Fatigue Strength, MPa | 190 | |
| 150 |
| Poisson's Ratio | 0.28 | |
| 0.28 |
| Shear Modulus, GPa | 77 | |
| 80 |
| Tensile Strength: Ultimate (UTS), MPa | 480 | |
| 500 |
| Tensile Strength: Yield (Proof), MPa | 200 | |
| 190 |
Thermal Properties
| Latent Heat of Fusion, J/g | 310 | |
| 310 |
| Maximum Temperature: Corrosion, °C | 430 | |
| 430 |
| Maximum Temperature: Mechanical, °C | 1100 | |
| 1100 |
| Melting Completion (Liquidus), °C | 1410 | |
| 1450 |
| Melting Onset (Solidus), °C | 1450 | |
| 1400 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 21 | |
| 13 |
| Thermal Expansion, µm/m-K | 15 | |
| 16 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 1.6 | |
| 1.7 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 1.8 | |
| 1.9 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 32 | |
| 31 |
| Density, g/cm3 | 8.1 | |
| 8.1 |
| Embodied Carbon, kg CO2/kg material | 5.6 | |
| 5.9 |
| Embodied Energy, MJ/kg | 78 | |
| 80 |
| Embodied Water, L/kg | 210 | |
| 200 |
Common Calculations
| PREN (Pitting Resistance) | 29 | |
| 38 |
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 170 | |
| 130 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 110 | |
| 89 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 17 | |
| 17 |
| Strength to Weight: Bending, points | 17 | |
| 17 |
| Thermal Diffusivity, mm2/s | 5.6 | |
| 3.4 |
| Thermal Shock Resistance, points | 12 | |
| 11 |
Alloy Composition
| Carbon (C), % | 0 to 0.070 | |
| 0 to 0.030 |
| Chromium (Cr), % | 19 to 22 | |
| 20 to 22 |
| Copper (Cu), % | 3.0 to 4.0 | |
| 0 |
| Iron (Fe), % | 37.4 to 48.5 | |
| 42.4 to 52.5 |
| Manganese (Mn), % | 0 to 1.5 | |
| 0 to 2.0 |
| Molybdenum (Mo), % | 2.0 to 3.0 | |
| 4.5 to 5.5 |
| Nickel (Ni), % | 27.5 to 30.5 | |
| 23 to 27 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.030 |
| Silicon (Si), % | 0 to 1.5 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.040 | |
| 0 to 0.030 |