EN 1.4057 +QT800 Steel vs. EN 1.4057 +QT900 Steel
Both EN 1.4057 +QT800 steel and EN 1.4057 +QT900 steel are variants of the same material. They share alloy composition and many physical properties, but develop different mechanical properties as a result of different processing.
For each property being compared, the top bar is EN 1.4057 +QT800 steel and the bottom bar is EN 1.4057 +QT900 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 200 | |
| 200 |
| Elongation at Break, % | 12 | |
| 11 |
| Fatigue Strength, MPa | 380 | |
| 430 |
| Impact Strength: V-Notched Charpy, J | 21 | |
| 16 |
| Poisson's Ratio | 0.28 | |
| 0.28 |
| Shear Modulus, GPa | 77 | |
| 77 |
| Shear Strength, MPa | 530 | |
| 580 |
| Tensile Strength: Ultimate (UTS), MPa | 880 | |
| 980 |
| Tensile Strength: Yield (Proof), MPa | 680 | |
| 790 |
Thermal Properties
| Latent Heat of Fusion, J/g | 280 | |
| 280 |
| Maximum Temperature: Corrosion, °C | 400 | |
| 400 |
| Maximum Temperature: Mechanical, °C | 850 | |
| 850 |
| Melting Completion (Liquidus), °C | 1440 | |
| 1440 |
| Melting Onset (Solidus), °C | 1390 | |
| 1390 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 480 |
| Thermal Conductivity, W/m-K | 25 | |
| 25 |
| Thermal Expansion, µm/m-K | 10 | |
| 10 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 2.5 | |
| 2.5 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.9 | |
| 2.9 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 9.5 | |
| 9.5 |
| Density, g/cm3 | 7.7 | |
| 7.7 |
| Embodied Carbon, kg CO2/kg material | 2.2 | |
| 2.2 |
| Embodied Energy, MJ/kg | 32 | |
| 32 |
| Embodied Water, L/kg | 120 | |
| 120 |
Common Calculations
| PREN (Pitting Resistance) | 16 | |
| 16 |
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 96 | |
| 98 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 1180 | |
| 1610 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 25 | |
| 25 |
| Strength to Weight: Axial, points | 31 | |
| 35 |
| Strength to Weight: Bending, points | 26 | |
| 28 |
| Thermal Diffusivity, mm2/s | 6.7 | |
| 6.7 |
| Thermal Shock Resistance, points | 31 | |
| 35 |
Alloy Composition
| Carbon (C), % | 0.12 to 0.22 | |
| 0.12 to 0.22 |
| Chromium (Cr), % | 15 to 17 | |
| 15 to 17 |
| Iron (Fe), % | 77.7 to 83.4 | |
| 77.7 to 83.4 |
| Manganese (Mn), % | 0 to 1.5 | |
| 0 to 1.5 |
| Nickel (Ni), % | 1.5 to 2.5 | |
| 1.5 to 2.5 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.015 | |
| 0 to 0.015 |