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Learn The Manufacturing Process Of 4340 Round Bar

Nickel-chromium-molybdenum alloy steel 4340 is a material that achieves high performance through strict manufacturing and processing technology. The process technology used for 4340 steel round bars is different from that used for steel plates. The manufacturing process of 4340 round bar involves multiple key steps and technologies. And compared with 4340 steel plates, 4340 round bars are often widely used in multiple industrial fields. Therefore, this article will introduce the manufacturing process of 4340 round bars in detail to ensure its best performance and better application in your project.

High Quality Raw Materials

First of all, the selection of raw materials for Songshun 4340 round bar is strictly in accordance with the standards. When selecting materials, we strictly consider factors such as the alloy composition, smelting technology, purity and uniformity of the raw materials to ensure the high purity of the raw materials, thereby ensuring the quality of the steel.

High Precision Smelting

If the raw material you choose is the blank of 4340 round bar, the next step is heating, forging or rolling; if the raw material you choose is iron ore, scrap steel and alloy elements, this requires smelting.

In this process, we put the raw materials into an electric arc furnace to melt the metal at high temperature to form liquid steel, and then use refining processes such as vacuum degassing to remove impurities and gases in the molten steel to improve the purity of the molten steel.

Forming Process - Casting, Forging Or Rolling

According to different customer needs, Songshun can provide various processes for manufacturing 4340 round bar to create steel that meets your needs or even exceeds your expectations.

1.Casting (molten steel): After refining, the pure molten steel is poured into the mold for casting and casting into ingots. This step is the key link in manufacturing 4340 round bar and prepares for subsequent processing. This process only forms the 4340 billet, and forging or rolling is required later.

2.Forging (bill or ingot): This process can be achieved through different methods, the most common of which are hot forging or cold forging. Hot forging is to forge billets or ingots at high temperature and pressure to achieve the required 4340 steel shape and size. This process can better improve the uniformity and plasticity of the material, which is conducive to the formation of a fine grain structure, and improve the strength and wear resistance of the material. Cold forging is carried out at a lower temperature, which can make the material obtain higher strength and hardness, but the plasticity is slightly inferior to hot forging. At Songshun, the method used depends on the specific requirements of the customer’s 4340 round bar properties, cost and processing technology.

3.Rolling: At Songshun, we can also use the continuous casting and rolling process, which is a steel rolling process that directly enters the hot rolling unit to roll and form the continuous casting billet after being kept warm in the soaking furnace for a certain period of time without going through the traditional cooling process. Rolling is to roll the 4340 round bar billet through the rolling mill for multiple times, plastic deformation, and finally form a round bar with a circular cross-section of the required size. The rolled round bar can also be straightened by a straightening machine to achieve the required straightness.

Optimized Heat Treatment Process

After the 4340 steel round bar is formed, it is subjected to heat treatment process, which is the key to improving the performance of steel. According to the different needs of customers, the temperature and time of normalizing, spheroidizing annealing, hardening, tempering, as well as the cooling medium and time are optimized to improve the lattice structure and mechanical properties of the steel, ensuring that the 4340 round bar achieves high performance and quality.

Various Processing Methods And Surface Treatments

The processing is mainly to improve the dimensional accuracy and surface quality of 4340 round bar and meet customer needs. In Songshun, we provide various rough processing, fine processing and surface treatment, including grinding, milling, turning, polishing, peeling, straightening, drilling, pickling, sandblasting, chrome plating, etc., to ensure that the surface of the material is smooth and the size is accurate to meet the use requirements.

Strict Quality Inspection And Packaging

Strict quality inspection is very important in the process of manufacturing aisi 4340 round bars. Including chemical analysis, dimensional accuracy, non-destructive testing, hardness, metallographic structure, etc., to ensure that the quality of each 4340 round bar meets the requirements. Finally, the round bars that pass the inspection will be properly packaged, and customized packaging can also be used to ensure the quality of the round bars during transportation and storage.

The above are the main steps and processes of Songshun in manufacturing 4340 round bar. It involves multiple complex technologies, and each step requires precise control and strict monitoring to ensure the quality and performance of the material. Therefore, if you need to choose better 4340 steel round bar, Songshun will be your best choice. As the technology continues to improve, we will continue to optimize the manufacturing process of 4340 steel to adapt to the increasingly stringent application environment, market and customer needs.


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