4340 Steel
Our 4340 alloy steel forgings have high strength, high toughness, good machinability, and good corrosion resistance. 4340 forged steel parts have excellent overall performance and are widely used in heavy machinery, aerospace, automotive, energy, shipbuilding, and general machinery industries.
4340 Steel Forgings Applications:
4340 alloy steel forgings have high strength, high toughness, good machinability, and good corrosion resistance. 4340 alloy steel forgings are ideal blank materials for the manufacturing of large-sized, high-load-bearing components. 4340 forged steel parts have excellent overall performance and are widely used in heavy machinery, aerospace, automotive, energy, shipbuilding, and general machinery industries.
- Heavy Machinery: Large gears, driving shafts, hydraulic cylinder parts, tracks, fasteners.
- Aerospace Industry: Aircraft landing gear, high-duty structural components, turbine shafts.
- Automotive Industry: Crankshafts, axle shafts, gears, connecting rods, heavy-duty fasteners.
- Oil & Gas Industry: Drilling collars, shafts, valve bodies, wellhead equipment, and fishing tools.
- Ship Building Industry: Main shafts, rudder stocks, winch gears, marine propulsion parts.
- General Engineering Industry: Driving gears, heavy-duty shafts, axles, spindles.
4340 Forged Steel Features：
4340 forged steel has high strength, high toughness, wear resistance, high temperature stability, good machinability, and corrosion resistance.
- High Strength & High Toughness:
4340 forged steel has the Ni-Cr-Mo composition. After heat treatment, 4340 steel forgings have high tensile strength (typically not less than 980 MPa) and yield strength (not less than 835 MPa), while maintaining good plasticity (elongation can reach over 12%) and good impact toughness. 4140 steel forgings are less prone to fracture under high-stress or impact loading.
- High Hardenability:
4340 forged steel has deep hardenability. 4340 steel forgings exhibit uniform hardening in large cross-section parts, ensuring high strength and good durability throughout.
- Excellent Fatigue Resistance:
4340 forged steel exhibits excellent fatigue resistance under cyclic loading, making 4340 steel forgings suitable for dynamic loading environments, such as gears and shafts.
- Good Wear Resistance:
4340 forged steel parts have good wear and abrasion resistance in their hardened state.
- Good Machinability:
4340 steel forgings can be machined using conventional methods, especially in the annealed or pre-hardened condition.
- High Corrosion Resistance & High-Temperature Stability:
4340 steel forgings have good corrosion resistance and high-temperature strength due to the alloying elements chromium, nickel, and molybdenum. 4340 forged steel parts are suitable for harsh environments.
- Good Weldability:
We can weld 4340 steel using gas or arc welding.
- Heat Treatable:
4340 forged steel is responsive to hardening, tempering, and surface hardening (nitriding, induction hardening).
4340 Steel Properties
AISI 4340 alloy steel physical properties information table.
| Properties | Metric | Metric Imperial |
|---|---|---|
|
Density |
7.85 g/cm3 |
0.284 lb/in³ |
|
Melting point |
1427°C |
2600°F |
AISI 4340 alloy steel mechanical properties information table.
| Properties | Metric | Metric Imperial |
|---|---|---|
|
Tensile strength |
745 MPa |
10800 psi |
|
Yield strength |
470 MPa |
68200 psi |
|
Elongation at break (in 50 mm) |
22% |
22% |
|
Hardness, Brinell |
217 |
217 |
|
Machinability (based on AISI 1212 as 100 machinability) |
50 |
50 |
AISI 4340 alloy steel thermal properties information table.
| Properties | Metric | Metric Imperial |
|---|---|---|
|
Thermal expansion coefficient (@ 0-100°C/32-212°F) |
12.3 µm/m°C |
6.83 µin/in°F |
|
Thermal conductivity (@ 100°C) |
44.5 W/mK |
309 BTU in/hr.ft².°F |
4340 Steel Chemical Composition
4340 steel contains 0.37%-0.43% carbon, 0.70%-0.90% chromium, 1.65%-2.00% nickel, and 0.20%-0.30% molybdenum.
| Steel Grade | Carbon, C | Silicon, Si | Manganese, Mn | Phosphorous, P | Sulfur, S | Chromium, Cr | Molybdenum, Mo | Nickel, Ni | Iron, Fe |
|---|---|---|---|---|---|---|---|---|---|
|
4340 |
0.370 – 0.430 |
0.150 – 0.300 |
0.600 – 0.800 |
≤ 0.0350 |
≤0.040 |
0.700 – 0.900 |
0.200 – 0.300 |
1.65 – 2.00 |
Balance |
4340 Steel Equivalent
AISI 4340 alloy steel chemical composition information for reference.
| EU EN | USA |
Germany DIN,WNr |
France AFNOR |
Italy UNI |
Inter ISO |
|---|---|---|---|---|---|
|
34CrNiMo6 (1.6582) |
4340 |
34CrNiMo6 |
35NCD6 |
35CrNiMo6 |
36CrNiMo6 |
4340 Steel Forgings Manufacturer
We are a leading 4340 steel forgings supplier and manufacturer in China.
Our 4340 steel forgings have high strength, high toughness, good machinability, good corrosion resistance, and high temperature stability.
Our 4340 steel forgings are widely used in the heavy machinery, aerospace, automotive, energy, shipbuilding, and general machinery industries.
Our 4340 forgings are the ideal blank materials for the manufacturing of large, heavy-duty parts, such as gears, shafts, and fasteners.
Feel free to contact us for price information about our 4340 steel forgings.
4140 Steel Shaft Forgings
Open Die Forging & Ring Rolling Forging
We possess multiple free forging machines and ring rolling machines. Our free forging machines includes a 1-ton air hammer, a 2-ton hydraulic hammer, a 5-ton hydraulic forging machine, a 3500-ton hydraulic forging machine, and multiple ring rolling machines.
Our custom forged parts can weigh up to 20,000 kg and have a maximum length of 20 m. The outer diameter of the forged rings can reach 4.5 m.
Why Choose Shanghai FAR WELL?
We are professional steel forging company in China for forged steel parts. Our factory is 200KM away from Shanghai Port. We are a modern management steel forging company targeting the international market.
- One Station Service
- Quality Products
- Competitive Price
- Professional Service
- On-time Delivery
Custom Forged Parts
