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Alloy steel 4340
Material type: Metal, High hardness, High strength
Alloy steel 4340 is a heat treatable and low alloy steel containing chromium, nickel and molybdenum. It has high toughness and strength in the heat treated condition.
Process compatibility
Material Color
Silver gray
Material advantages
Alloy steel 4340 can be heat treated to high strength levels while maintaining good toughness, wear resistance and fatigue strength levels, combined with good atmospheric corrosion resistance, and strength.
Material shortcomings
-
Recommended description
Good toughness, wear resistance and fatigue strength levels, combined with good atmospheric corrosion resistance, and strength.
Properties
| Name | |
|---|---|
| Tensile strength | 820MPa |
| Yield strength | 525MPa |
| Density | 7.85 g/cc |
| Hardness | 24-53HRC |
| Elongation at Break | 22% |
| Modulus of elasticity | 213GPa |
| Shear modulus | 80GPa |
| Thermal expansion coefficent | 11.5 - 13 10^-6 ºC |
| Melting point | 1427°C |
Common applications
• Power transmission gears and shafts
• Aircraft landing gear
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