ACI-ASTM CF8M Steel vs. ACI-ASTM CN7M Steel
Both ACI-ASTM CF8M steel and ACI-ASTM CN7M steel are iron alloys. Both are furnished in the heat treated (HT) condition. They have 77% of their average alloy composition in common.
For each property being compared, the top bar is ACI-ASTM CF8M steel and the bottom bar is ACI-ASTM CN7M steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 170 | |
| 140 |
| Elastic (Young's, Tensile) Modulus, GPa | 200 | |
| 200 |
| Elongation at Break, % | 50 | |
| 44 |
| Fatigue Strength, MPa | 280 | |
| 190 |
| Poisson's Ratio | 0.28 | |
| 0.28 |
| Shear Modulus, GPa | 78 | |
| 77 |
| Tensile Strength: Ultimate (UTS), MPa | 540 | |
| 480 |
| Tensile Strength: Yield (Proof), MPa | 290 | |
| 200 |
Thermal Properties
| Latent Heat of Fusion, J/g | 300 | |
| 310 |
| Maximum Temperature: Corrosion, °C | 420 | |
| 430 |
| Maximum Temperature: Mechanical, °C | 1000 | |
| 1100 |
| Melting Completion (Liquidus), °C | 1440 | |
| 1410 |
| Melting Onset (Solidus), °C | 1400 | |
| 1450 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 470 |
| Thermal Conductivity, W/m-K | 16 | |
| 21 |
| Thermal Expansion, µm/m-K | 16 | |
| 15 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 2.0 | |
| 1.6 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.3 | |
| 1.8 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 19 | |
| 32 |
| Density, g/cm3 | 7.8 | |
| 8.1 |
| Embodied Carbon, kg CO2/kg material | 3.8 | |
| 5.6 |
| Embodied Energy, MJ/kg | 53 | |
| 78 |
| Embodied Water, L/kg | 160 | |
| 210 |
Common Calculations
| PREN (Pitting Resistance) | 28 | |
| 29 |
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 230 | |
| 170 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 210 | |
| 110 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 25 | |
| 24 |
| Strength to Weight: Axial, points | 19 | |
| 17 |
| Strength to Weight: Bending, points | 19 | |
| 17 |
| Thermal Diffusivity, mm2/s | 4.3 | |
| 5.6 |
| Thermal Shock Resistance, points | 12 | |
| 12 |
Alloy Composition
| Carbon (C), % | 0 to 0.080 | |
| 0 to 0.070 |
| Chromium (Cr), % | 18 to 21 | |
| 19 to 22 |
| Copper (Cu), % | 0 | |
| 3.0 to 4.0 |
| Iron (Fe), % | 60.3 to 71 | |
| 37.4 to 48.5 |
| Manganese (Mn), % | 0 to 1.5 | |
| 0 to 1.5 |
| Molybdenum (Mo), % | 2.0 to 3.0 | |
| 2.0 to 3.0 |
| Nickel (Ni), % | 9.0 to 12 | |
| 27.5 to 30.5 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 2.0 | |
| 0 to 1.5 |
| Sulfur (S), % | 0 to 0.040 | |
| 0 to 0.040 |