Songshun Steel & TOP Steel Manufacturer Supplier in China

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One of the leading 4340 round rod suppliers in China-Songshun Steel

4340 round bar is a commonly used high-strength alloy steel and is widely used in aviation, automobiles, ships and other fields. These fields usually have strict quality requirements for steel, so it is particularly important to find reliable 4340 steel round bar suppliers. So if you want to purchase 4340 steel, Songshun Steel will be your ideal partner.

As one of the leading 4340 round bar suppliers in China, Songshun Steel is the best in terms of quality, testing, service and price. Especially in terms of product quality, we have always adhered to high requirements, high standards and high quality to provide customers with the best 4340 steel. The following are the chemical composition, performance and specifications of 4340 round rods provided by Songshun Steel.

1.Steel Equivalent

Equivalent grade of alloy steel 4340 round bar:
*China GB /T 3077-1999 standard: GB 40CrNiMoA / GB 45CrNiMoVA
*US ASTM A29/A29M-2005 standard: AISI/SAE/ASTM 4340
*German EN 10250-3-1999 standard: DIN 36NiCrMo4/DIN 1.6511
*Japanese JIS G 4053-2003 standard: JIS SNCM439

2.Chemical Composition

STAND C(%) Mn(%) P(%) S(%) Si(%) Cr(%) Mo(%) Ni(%)
ASTM A29 / A29M-05 0.38-0.43 0.60-0.80 ≤0.035 ≤0.040 0.15-0.35 0.70-0.90 0.20-0.30 1.65-2.00
EN 10263/4-2001 0.38-0.44 0.60-0.90 ≤0.025 ≤0.025 ≤0.30 0.70-0.90 0.15-0.30 1.65-2.00
JIS G4053-2008 0.36-0.43 0.60-0.90 ≤0.030 ≤0.030 0.15-0.35 0.60-1.00 0.15-0.30 1.60-2.00
ISO 683/18-1996 0.32-0.40 0.50-0.80 ≤0.035 ≤0.035 0.10-0.40 0.90-1.20 0.15-0.30 0.90-1.20

3.Performance Characteristics

It is very critical for 4340 round rod suppliers to ensure that it has excellent performance, which is an important criterion for determining product quality.

(1) High strength and high hardness: After quenching and tempering, 4340 steel obtains higher hardness and has excellent yield strength, tensile strength and fatigue resistance.

(2) Good wear resistance and toughness: The high hardness of 4340 steel round bar provides it with better wear resistance, and it also has good toughness and fracture toughness, which can maintain stable performance in extreme working environments and effectively prevent friction, wear, fracture and rupture.

(3) Outstanding hardenability and stability against overheating: 4340 steel can form a uniform martensite structure in a short time and maintain its mechanical properties and structural stability under high temperature conditions.

In addition to the above properties, AISI 4340 steel also has good corrosion resistance, good plasticity, good heat resistance, etc.


Among the many 4340 round bar suppliers, Songshun Steel can provide the most complete range of 4340 round bar specifications.
Diameter: Ø2mm – 3000mm; (*Φ20-300mm in stock, immediate shipment)
Length: 20000mm Max;
Other Specifications: support customized services;

In addition to product quality, understanding the equipment, process technology, production capacity level, and services of the 4340 round bar supplier is also a factor to consider when evaluating 4340 round bar suppliers.

In Songshun, as one of the leading 4340 round bar suppliers in China, we ensure the quality of our products, continuously improve production efficiency, reduce costs, and provide you with the most competitive prices. And we have our own processing plant, providing various processing services, as well as a large warehouse, with the ability to meet large batch orders and deliver on time. It can also respond to customer needs in a timely manner and provide a full range of pre-sales, sales and after-sales services, and can respond and handle quickly.

In short, if you are looking for suitable of 4340 steel round bar suppliers, considering multiple factors such as product quality, production capacity, service system, price, etc., Songshun Steel is your best choice to provide you with the best 4340 Steel round bar.

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Dongguan Songshun Mould Steel Co., Ltd.

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