4140 Steel Data
| Carbon | 0.38 - 0.43 |
| Chromium | 0.8 - 1.1 |
| Iron | Balance |
| Manganese | 0.75 - 1 |
| Molybdenum | 0.15 - 0.25 |
| Phosphorus | 0.035 max |
| Silicon | 0.15 - 0.35 |
| Sulphur | 0.04 max |
| Density | 0.284 lb/in3 |
| Tensile Strength, | 156000 psi |
| Tensile Strength, Yield | 143000 psi |
| Elongation at Break | 15.5 % |
| Reduction of Area | 56.9 % |
| Modulus of Elasticity | 29700 ksi |
| Poisson's Ratio | 0.29 |
| Shear Modulus | 11600 ksi |
| Electrical Resistivity | 2.2e-005 ohm-cm |
| CTE, linear 20°C | 6.78 μin/in-°F |
| CTE, linear 250°C | 7.61 μin/in-°F |
| CTE, linear 500°C | 8.11 μin/in-°F |
| Specific Heat Capacity at Elevated Temperature | 0.113 BTU/lb-°F |
| Thermal Conductivity | 296 BTU-in/hr-ft2-°F |
| Thermal Conductivity at Elevated Temperature | 229 BTU-in/hr-ft2-°F |