Annealing Hot Rolled Steel Bar Tensile Strength ≥1080MPa For Mechanical SAE4140

1.7225 / SCM440 / SAE4140 Hot Rolled Alloy Steel Round Bar for Mechanical


1, Equivalent grades:

2, Perform Standard: GB/T 3077-1999

3, Available size(mm)

Listed specifications are only typical grades; products of required specifications can be developed/produced per international, Chinese or industry standards, or based on agreements with customers.

4, Application:
It used for section large forgings, such as locomotive traction gears, with supercharger drive gear,
the rear axle, the connecting rod and the spring load greatly clip,oil drill pipe joints and fishing tools,etc.

5, Mechanical Properties:
Tensile strength:σb (MPa):≥1080(110)
Yield strength:σs (MPa):≥930(95)
Elongation:δ5 (%):≥12
Section shrinkage:ψ (%):≥45
Impact work:Akv (J):≥63
Impact toughness value:αkv (J/cm²):≥78(8)


6, Heat treatment:

7, Feature:
1) Weldability suffers with increasing chromium content;
2) High temperature strength and high pressure hydrogenation properties are promoted by chromium and molybdenum;
3) Molybdenum significantly reduces temper brittleness;
4) Chromium renders steel oil hardenable and increase hardenability;
5) Chromium molybdenum high tensile steel with yield strength of 550N/mm2;

8, Ready Stock:
Round Bar diameter 35-260mm.All the sizes as require can be customerized as fresh production with MOQ.

9, Delivery state:
Hot rolled, black, hardness or tempered hardness:28-34 HRC.
Annealing:HBS<=235.

10, Delivery time:
For abundant stock, 15-20 days.For customized products, 30-50 days.
We have full set of equipement (sawing machine/grinding/polishing machine) to make customer's specification.

11, Our service:

Guangzhou ChangFeng Steel Co., Ltd. is a professional special steel company, which specialized in exporting mould steel products based in China.With twenty years experience in special steel industry, our main products are Plastic Mould Steel, Hot Work Mould Steel, Cold Work Mould Steel, Alloy Structural Steel, Tool Steel, Stainless Steel, Carbon Steel and Forged Block.

To ensure provide high quality products to customers, we have close cooperation with many Chinese first class special steel enterprises, including Baosteel Group, Dongbei Special Steel, Changcheng Special Steel, Hongsheng Heavy Industry, Xingcheng Special Steel, Daye Special Steel. We have thousand tons of stock materials in our own factory and also can provide processing services to customers. We are full of export experience for many years, the product covers America, Germany, France, Italy, Turkey, Singapore, Thailand, Malaysia, Vietnam, Taiwan, and Middle-East.

After years of development, the company has established a complete quality management and export service system. We have a group of experienced and competent elites and is capable of offering the best service to clients. Our company equips with large-sized Vertical saw machines, Horizontal saw machines, Milling machines, Grinding machines and other advanced equipments to provide customers with cutting and other processing services. All the products should be inspected the metallographic analysis, hardness, ultrasonic flaw detection and other strict inspection processes, which meet the standards of DIN, AISI, JIS and GB to ensure their function and quality.

Our company keeps the principle of “sincerely cooperation, endless striving for perfection”. We desire to establish the long-term mutual beneficial and win-win relationship with clients all over the world.