AISI 4140 is a versatile chromium-molybdenum alloy steel with excellent hardenability and comprehensive mechanical properties. It features high tensile strength, good toughness, outstanding wear resistance and fatigue strength after quenching and tempering heat treatment. With stable mechanical performance and easy machining, it is widely used for gears, shafts, bolts, hydraulic parts, machinery structural components and high-load industrial parts.

Advantage

1.Excellent hardenability, uniform hardness and strength after heat treatment 2.High toughness and impact resistance, suitable for heavy-load dynamic working conditions 3.Great wear resistance and fatigue strength for long-term mechanical operation 4.Fine machinability and stable dimensional performance for various precision processing

Ingredient

• C
• 0.38 ~ 0.43
• Cr
• 0.80 ~ 1.10
• Mo
• 0.15 ~ 0.25
• Mn
• 0.75 ~ 1.00
• Si
• 0.15 ~ 0.35
• P
• ≤0.035
• S
• ≤0.040
• Fe
• Balance

• Board
• Stick
• Pipe

Title

4140 Board

Size

0.5mm – 100mm

Length

1000mm – 6000mm (customizable)

Production

Hot rolled + Annealed

Surface

Pickled / 2B / Polished

Processing

Hot rolled + Annealed

Standard

• USA
• ASTM A829 / AISI 4140
• China
• GB/T 3274‑2017、GB/T 11251‑2021

Mechanics

• STATE
• RP
• YIELD
• EXTEND
• SHRINK
• HARDNESS
• IMPACT
• Annealed
• ≥1020 MPa
• ≥860 MPa
• ≥12 %
• ≥40 %
• ≤321 HBW
• ≥20 J
• Annealed
• ≥980 MPa
• ≥820 MPa
• ≥12 %
• ≥40 %
• ≤321 HBW
• ≥20 J

• STATE
• Annealed
• RP
• ≥1020 MPa
• YIELD
• ≥860 MPa
• EXTEND
• ≥12 %
• SHRINK
• ≥40 %
• HARDNESS
• ≤321 HBW
• IMPACT
• ≥20 J
• STATE
• Annealed
• RP
• ≥980 MPa
• YIELD
• ≥820 MPa
• EXTEND
• ≥12 %
• SHRINK
• ≥40 %
• HARDNESS
• ≤321 HBW
• IMPACT
• ≥20 J

Title

4140 Stick

Size

8mm – 300mm

Length

1000mm – 6000mm (customizable)

Production

Hot rolled + Annealed

Surface

Black / Peeled / Polished

Processing

Hot rolled + Annealed

Standard

• USA
• ASTM A322 / AISI 4140
• China
• GB/T 3077‑2015、GB/T 4356‑2021

Mechanics

• STATE
• RP
• YIELD
• EXTEND
• SHRINK
• HARDNESS
• IMPACT
• Annealed
• ≥1020 MPa
• ≥860 MPa
• ≥12 %
• ≥40 %
• ≤321 HBW
• ≥20 J
• Annealed
• ≥980 MPa
• ≥820 MPa
• ≥12 %
• ≥40 %
• ≤321 HBW
• ≥20 J

• STATE
• Annealed
• RP
• ≥1020 MPa
• YIELD
• ≥860 MPa
• EXTEND
• ≥12 %
• SHRINK
• ≥40 %
• HARDNESS
• ≤321 HBW
• IMPACT
• ≥20 J
• STATE
• Annealed
• RP
• ≥980 MPa
• YIELD
• ≥820 MPa
• EXTEND
• ≥12 %
• SHRINK
• ≥40 %
• HARDNESS
• ≤321 HBW
• IMPACT
• ≥20 J

Title

4140 Pipe

Size

6mm – 500mm OD, 1mm – 50mm WT

Length

1000mm – 12000mm (customizable)

Production

Hot finished + Annealed / Cold drawn + Annealed

Surface

Pickled / Bright annealed / Polished

Processing

Hot finished + Annealed / Cold drawn + Annealed

Standard

• USA
• ASTM A519 / AISI 4140
• China
• GB/T 8162‑2018、GB/T 8163‑2018

Mechanics

• STATE
• RP
• YIELD
• EXTEND
• SHRINK
• HARDNESS
• IMPACT
• Annealed
• ≥1020 MPa
• ≥860 MPa
• ≥12 %
• ≥40 %
• ≤321 HBW
• ≥20 J
• Annealed
• ≥980 MPa
• ≥820 MPa
• ≥12 %
• ≥40 %
• ≤321 HBW
• ≥20 J

• STATE
• Annealed
• RP
• ≥1020 MPa
• YIELD
• ≥860 MPa
• EXTEND
• ≥12 %
• SHRINK
• ≥40 %
• HARDNESS
• ≤321 HBW
• IMPACT
• ≥20 J
• STATE
• Annealed
• RP
• ≥980 MPa
• YIELD
• ≥820 MPa
• EXTEND
• ≥12 %
• SHRINK
• ≥40 %
• HARDNESS
• ≤321 HBW
• IMPACT
• ≥20 J