EN 1.4903 +QT Steel vs. EN 1.4122 +QT750 Steel
Both EN 1.4903 +QT steel and EN 1.4122 +QT750 steel are iron alloys. Both are furnished in the quenched and tempered condition. They have a moderately high 91% of their average alloy composition in common.
For each property being compared, the top bar is EN 1.4903 +QT steel and the bottom bar is EN 1.4122 +QT750 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 200 |
| Elongation at Break, % | 21 | |
| 14 |
| Fatigue Strength, MPa | 330 | |
| 360 |
| Impact Strength: V-Notched Charpy, J | 46 | |
| 11 |
| Poisson's Ratio | 0.28 | |
| 0.28 |
| Shear Modulus, GPa | 75 | |
| 77 |
| Shear Strength, MPa | 420 | |
| 520 |
| Tensile Strength: Ultimate (UTS), MPa | 670 | |
| 850 |
| Tensile Strength: Yield (Proof), MPa | 500 | |
| 630 |
Thermal Properties
| Latent Heat of Fusion, J/g | 270 | |
| 280 |
| Maximum Temperature: Corrosion, °C | 380 | |
| 400 |
| Maximum Temperature: Mechanical, °C | 650 | |
| 870 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1440 |
| Melting Onset (Solidus), °C | 1420 | |
| 1400 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 480 |
| Thermal Conductivity, W/m-K | 26 | |
| 15 |
| Thermal Expansion, µm/m-K | 11 | |
| 10 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 3.4 | |
| 2.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 4.0 | |
| 2.5 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 7.0 | |
| 9.5 |
| Density, g/cm3 | 7.8 | |
| 7.7 |
| Embodied Carbon, kg CO2/kg material | 2.6 | |
| 2.4 |
| Embodied Energy, MJ/kg | 36 | |
| 33 |
| Embodied Water, L/kg | 88 | |
| 120 |
Common Calculations
| PREN (Pitting Resistance) | 13 | |
| 20 |
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 130 | |
| 110 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 650 | |
| 1000 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 25 | |
| 25 |
| Strength to Weight: Axial, points | 24 | |
| 31 |
| Strength to Weight: Bending, points | 22 | |
| 26 |
| Thermal Diffusivity, mm2/s | 7.0 | |
| 4.0 |
| Thermal Shock Resistance, points | 23 | |
| 30 |
Alloy Composition
| Aluminum (Al), % | 0 to 0.040 | |
| 0 |
| Carbon (C), % | 0.080 to 0.12 | |
| 0.33 to 0.45 |
| Chromium (Cr), % | 8.0 to 9.5 | |
| 15.5 to 17.5 |
| Copper (Cu), % | 0 to 0.3 | |
| 0 |
| Iron (Fe), % | 87.1 to 90.5 | |
| 77.2 to 83.4 |
| Manganese (Mn), % | 0.3 to 0.6 | |
| 0 to 1.5 |
| Molybdenum (Mo), % | 0.85 to 1.1 | |
| 0.8 to 1.3 |
| Nickel (Ni), % | 0 to 0.4 | |
| 0 to 1.0 |
| Niobium (Nb), % | 0.060 to 0.1 | |
| 0 |
| Nitrogen (N), % | 0.030 to 0.070 | |
| 0 |
| Phosphorus (P), % | 0 to 0.025 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 0.5 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.015 | |
| 0 to 0.015 |
| Vanadium (V), % | 0.18 to 0.25 | |
| 0 |