4340 Alloy Steel Supplier

4340 Forging Service

4340 Alloy Steel

4340 alloy steel is a widely used material in the aerospace and manufacturing industry. Because of its excellent strength, toughness, and fatigue resistance, 4340 is very popular. 4340 alloy is a combination of iron, carbon, nickel, chromium, and molybdenum. This is a high-strength steel that is capable of withstanding high stresses and loads.

At Friend Metals Distributor, we offer 4340 alloy in a variety of forms including round bars, flat bars, plate and in various sizes, which allows our customers to choose the right size for their specific needs.

4340 alloy steel is remarkable for its capability to be subjected to heat treatment, and in doing so; its mechanical properties are further improved. Quenching and tempering, annealing, and normalizing are among the methods used in this process. By undergoing these processes, the hardness, strength, and ductility of the alloy are increased, making it a fitting choice for use in strenuous situations such as airplane landing gear pieces, engine parts or transmission components.

Friend Metals Co is dedicated to providing superior materials that stand up to the requirements of our customers. Our 4340 alloy has gone through intensive testing and inspection processes in order to meet our stringent quality standards. We value direct communication with our customers, understanding their needs so that we can suggest customized solutions that are precisely designed for them.


Call Us at 714-632-0140 or Toll-Free at 800-854-6777.

4340 Heat Treatment

Heat treatment is a crucial process for 4340 alloy, which can significantly improve its mechanical properties, including strength, hardness, and toughness. There are several heat treatment methods available for 4340 alloy steel, including quenching and tempering, annealing, and normalizing.

Applying the heat treatment process of quenching and tempering to 4340 alloy is a common technique. This process entails heating the steel up to an extreme temperature, usually between 1500-1600°F (815-870°C), and then rapidly cooling it with a medium such as oil or water. The quick cooling procedure leads to increased strength and hardness but also results in brittleness. To restore the material’s ductility, it is reheated to a lower temperature ranging from 300-1100°F (150-590°C) depending on desired mechanical properties. Furthermore, this reheating has the added benefit of eliminating internal pressures in the steel and enhancing its toughness.

At Friend Metals Co, we offer 4340 alloy steel that is suitable for all heat treatment methods, including quenching and tempering, annealing, and normalizing.

4330 Forging

4340 Forging

We offer 4340 alloys of high strength, great toughness and remarkable fatigue resistance that make it an ideal material for forging. Our 4340 steel comes in various sizes and shapes suited to your needs.

Shaping metal into a desired form is the main objective of the process known as Forging. To do so, pressure and heat must be applied to deform it accordingly. 4340 alloy is commonly used for this task when creating components that are under high stress, needing superb strength and toughness like crankshafts, gears and more.

Forging 4340 alloy typically involves being heated up to 1175-1230°C and then compressed in a press or hammered into shape. This hot forging process helps to refine its grain structure, making it stronger and more consistent overall. Therefore, this procedure is carried out with temperatures between 2150-2250°F.

Friend Metals Co is proud to provide superior-quality 4340 alloy steel for forging processes. We offer our customers a wide array of forms, such as flat and round bars, that are sure to suit any industry’s needs. In order to ensure the highest quality results, we subject each piece of 4340 alloy steel to precise testing and inspection.  

4330 Bar

4340 Bar

Our selection of alloys includes the 4340 grade, which is widely used due to its strength and versatility. We offer this material in various sizes and forms to accommodate each customer’s preferences.

4340 alloy is renowned for its durability and strength. The composition of chromium, nickel, molybdenum, imbues it with the ability to resist wear, oxidation at high temperatures, as well as corrosion.

Friend Metals Co is proud to offer 4340 alloy bars of different shapes and sizes. Our selection consists of round, square, and rectangular bars that are available in various lengths and measurements. We can even provide tailored cutting services for customers wanting a specific length or size.

Heat treatment of 4340 bars is a key factor to boosting the strength, hardness, and toughness. Common forms of this heat treatment include quenching and tempering, annealing, and normalizing – all of which aid in elevating the material’s mechanical properties. Due to such performance benefits, 4340 alloy is frequently employed in high-stress components including shafts, gears and other machine parts.

Friend Metals Co understands that meeting the expectations of customers is vital. That’s why our 4340 alloy bars are subject to rigorous testing and monitoring to guarantee they are up to mark.

Are you in need of a steel bar that will provide superior strength, toughness and wear resistance? Look no further than 4340 steel bars. Produced by Friend Metals Co, these bars are ideal for any high-stress application as they can resist corrosion too. Different sizes and forms are available to suit your particular needs – why not contact us today to explore our offerings?

4340 AlloyChemical Composition

The chemical composition of 4340 alloy is as follows:

  • Carbon (C): 0.38-0.43%
  • Silicon (Si): 0.15-0.35%
  • Manganese (Mn): 0.65-0.9%
  • Phosphorus (P): 0.035% max
  • Sulfur (S): 0.040% max
  • Chromium (Cr): 0.7-0.9%
  • Nickel (Ni): 1.65-2.00%
  • Molybdenum (Mo): 0.2-0.3%

A combination of chromium, nickel, molybdenum form an alloy that is popularly known as 4340 grade low-alloy high-strength in the field of steels. Possessing excellent resistance to wear and tear as well as corrosion caused by heat oxidation, this material also demonstrates enhanced strength and toughness due to its composition.

The 4340 alloy is known for its outstanding level of strength and tough-as-nails durability, thanks to a couple key components. At the head of the list are two primary alloying elements – namely, manganese and carbons – without which these properties wouldn’t be achievable. As well as this, silicon plays an important role in enhancing both strength and hardness.

AMS Number

AMS 6415


AMS 6414


AMS 6484


AMS 6409


AMS 6359


AMS  S5000




MIL S5000


Have Question?

For a free quote or To find out more about 4340 Alloy Steel, Call us on 714-632-0140

About Us

Friend Metals Co, is a leading steel distributor specializing in a wide range of steel products, including bar, forging, plate, and sheet materials.

© 2023 - Friend Metals Co.