4340 Steel Bar, Rod & Wire

4340 alloy steel bar is used heavily in the aerospace industry due to its ultra-high strength. When heat treated it is known for its toughness while preserving good fatigue strength. For highly stressed parts it is excellent choice. It can be machined by all customary methods. This material is available in both vacuum melt (VM) and air melt (AM).

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  • Aircraft Landing Gear
  • Power Transmission Gears
  • Structural Use Applications
Typical Chemical Properties
Minimum Properties Tensile Strength , psi 140,000
  Yield Strength, psi 120,000
  Elongation 14%
  Hardness Rc 32/39
Chemistry Carbon( C) .38 -.43%
  Chrome (Cr) 0.70- 0.90%
  Manganese (Mn) 0.60-0.80%
  Molybdenum (Mo) 0.20 - .30%
  Nickel ( Ni) 1.65-2.0%
  Phosphorus (P) 0.030%
  Sulphur (S) 0.040%
  Silicon (Si) 0.15- 0.35%

Shop 4340 Steel Bar, Rod & Wire

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