EN 1.4024 +QT550 Steel vs. EN 1.4024 +QT650 Steel
Both EN 1.4024 +QT550 steel and EN 1.4024 +QT650 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 1.4024 +QT550 steel and the bottom bar is EN 1.4024 +QT650 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 17 | |
| 15 |
| Fatigue Strength, MPa | 280 | |
| 300 |
| Poisson's Ratio | 0.28 | |
| 0.28 |
| Shear Modulus, GPa | 76 | |
| 76 |
| Shear Strength, MPa | 400 | |
| 460 |
| Tensile Strength: Ultimate (UTS), MPa | 650 | |
| 750 |
| Tensile Strength: Yield (Proof), MPa | 460 | |
| 510 |
Thermal Properties
| Latent Heat of Fusion, J/g | 270 | |
| 270 |
| Maximum Temperature: Corrosion, °C | 390 | |
| 390 |
| Maximum Temperature: Mechanical, °C | 760 | |
| 760 |
| Melting Completion (Liquidus), °C | 1440 | |
| 1440 |
| Melting Onset (Solidus), °C | 1400 | |
| 1400 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 480 |
| Thermal Conductivity, W/m-K | 30 | |
| 30 |
| Thermal Expansion, µm/m-K | 11 | |
| 11 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 2.9 | |
| 2.9 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 3.3 | |
| 3.3 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 7.0 | |
| 7.0 |
| Density, g/cm3 | 7.7 | |
| 7.7 |
| Embodied Carbon, kg CO2/kg material | 1.9 | |
| 1.9 |
| Embodied Energy, MJ/kg | 27 | |
| 27 |
| Embodied Water, L/kg | 100 | |
| 100 |
Common Calculations
| PREN (Pitting Resistance) | 13 | |
| 13 |
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 100 | |
| 98 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 530 | |
| 660 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 25 | |
| 25 |
| Strength to Weight: Axial, points | 23 | |
| 27 |
| Strength to Weight: Bending, points | 22 | |
| 24 |
| Thermal Diffusivity, mm2/s | 8.1 | |
| 8.1 |
| Thermal Shock Resistance, points | 23 | |
| 26 |
Alloy Composition
| Carbon (C), % | 0.12 to 0.17 | |
| 0.12 to 0.17 |
| Chromium (Cr), % | 12 to 14 | |
| 12 to 14 |
| Iron (Fe), % | 83.8 to 87.9 | |
| 83.8 to 87.9 |
| Manganese (Mn), % | 0 to 1.0 | |
| 0 to 1.0 |
| 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 |