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4340 Alloy Steel

4340 Alloy Steel Bar

AISI 4340 alloy steel is equipped with high fatigue resistance, high strength, and good machinability that make it suitable for a wide variety of applications.

4340 Alloy Steel4340 Alloy Steel (UNS G434000), a heat treatable low alloy steel with chromium and molybdenum content, is a suitable material for heat-treated conditions. The 4340 round bar exhibits excellent resistance to fatigue.

This alloy steel is typically known for its ability to obtain a high level of strength and toughness in the heat-treated conditions. Though being heat-treated, the steel rod can still maintain good toughness, fatigue strength levels, and wear resistance, coupled with exceptional resistance to atmospheric corrosion, and strength that’s up to around 600ᵒ F (315ᵒ C).

4340 Steel Round Bar Machining

AISI 4340 round bar can be machined with the use of conventional methods. The machining process is performed in normalized or annealed and tempered conditions. Having good ductility and formability in its annealed condition, this alloy steel can be formed or bent by spinning or pressing in its annealed state.

Heat treatment is necessary after forging to make the material suitable for any machining. This also helps to meet those mechanical property limits which are specified for the steel’s exact applications. Heat treatment can be done in several ways if defining optimum treatments, temperatures, and conditions are met.

UNS G434000 is a readily machinable alloy steel grade though having either spheroidized structure and coarse lamellar pearlitic structure or how complex the size is or amount of machining needs to be carried out. If suitability of the structure is a major concern, then the spheroidized structure should be obtained in the heat-treating condition.

UNS G434000 Steel Rods Application

4340 alloy steel is used in a wide variety of industrial and manufacturing applications and structural parts which include:

  • Aircraft landing gear
  • Power transmission gears and shafts
  • Commercial and military aircraft
  • Forged hydraulic
  • Machine tool applications
  • Forged steel crankshafts
  • Automotive systems

4340 Steel Bar Suppliers

We offer 4340 alloy steel with a full range of stock sizes in forging products, wire products, casting products, flat-rolled products, fasteners, piping components, tubular products, and structurals. We also do different machining operations to meet all your application requirements.

If you have some queries or want to have details about our services and product availability, you may contact us directly to talk to one of our steel sales experts. You can also get our free quote of the most competitive 4340 alloy steel prices!


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