EN 1.7720 Steel vs. EN 1.7379 Steel
Both EN 1.7720 steel and EN 1.7379 steel are iron alloys. Both are furnished in the quenched and tempered condition. They have a very high 97% of their average alloy composition in common.
For each property being compared, the top bar is EN 1.7720 steel and the bottom bar is EN 1.7379 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 180 | |
| 200 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 19 | |
| 21 |
| Fatigue Strength, MPa | 230 | |
| 320 |
| Impact Strength: V-Notched Charpy, J | 30 | |
| 45 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 73 | |
| 74 |
| Tensile Strength: Ultimate (UTS), MPa | 590 | |
| 670 |
| Tensile Strength: Yield (Proof), MPa | 340 | |
| 460 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 260 |
| Maximum Temperature: Mechanical, °C | 410 | |
| 460 |
| Melting Completion (Liquidus), °C | 1470 | |
| 1470 |
| Melting Onset (Solidus), °C | 1430 | |
| 1420 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 40 | |
| 39 |
| Thermal Expansion, µm/m-K | 13 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.3 | |
| 7.6 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.4 | |
| 8.8 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 2.8 | |
| 3.8 |
| Density, g/cm3 | 7.9 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 2.2 | |
| 1.8 |
| Embodied Energy, MJ/kg | 30 | |
| 23 |
| Embodied Water, L/kg | 51 | |
| 59 |
Common Calculations
| PREN (Pitting Resistance) | 2.1 | |
| 5.7 |
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 97 | |
| 120 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 300 | |
| 550 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 21 | |
| 24 |
| Strength to Weight: Bending, points | 20 | |
| 22 |
| Thermal Diffusivity, mm2/s | 11 | |
| 11 |
| Thermal Shock Resistance, points | 17 | |
| 19 |
Alloy Composition
| Carbon (C), % | 0.1 to 0.15 | |
| 0.13 to 0.2 |
| Chromium (Cr), % | 0.3 to 0.5 | |
| 2.0 to 2.5 |
| Copper (Cu), % | 0 to 0.3 | |
| 0 |
| Iron (Fe), % | 96.6 to 98.6 | |
| 94.5 to 96.5 |
| Manganese (Mn), % | 0.4 to 0.7 | |
| 0.5 to 0.9 |
| Molybdenum (Mo), % | 0.4 to 0.6 | |
| 0.9 to 1.2 |
| Nickel (Ni), % | 0 to 0.4 | |
| 0 |
| Phosphorus (P), % | 0 to 0.030 | |
| 0 to 0.025 |
| Silicon (Si), % | 0 to 0.45 | |
| 0 to 0.6 |
| Sulfur (S), % | 0 to 0.020 | |
| 0 to 0.030 |
| Vanadium (V), % | 0.22 to 0.3 | |
| 0 |