8620 is a low-carbon nickel-chromium-molybdenum alloy steel designed for carburizing and case hardening. It features excellent toughness, good core ductility and fine grain structure. After carburizing, quenching and tempering, the surface gains high hardness and wear resistance while the core remains tough to withstand impact and heavy loads. It has great machinability and stable heat treatment performance, commonly used for gears, pinions, shafts, sprockets and various transmission mechanical

Advantage

1.Perfect combination of hard wear-resistant surface and tough impact-resistant core 2.Excellent carburizing performance and uniform case depth after heat treatment 3.Fine grain structure, low distortion and stable dimensional accuracy 4.Good machinability and cost efficiency for mass mechanical component production

Ingredient

• C
• 0.18 ~ 0.23
• Ni
• 0.40 ~ 0.70
• Cr
• 0.40 ~ 0.60
• Mo
• 0.15 ~ 0.25
• Mn
• 0.70 ~ 0.90
• Si
• 0.15 ~ 0.35
• P
• ≤0.035
• S
• ≤0.040
• Fe
• Balance

Standard

• USA
• ASTM A322 / AISI 8620
• CHINA
• GB/T 3077‑2015、GB/T 4356‑2021

Mechanics

• STATE
• RP
• YIELD
• EXTEND
• SHRINK
• HARDNESS
• IMPACT
• Annealed
• ≥635 MPa
• ≥390 MPa
• ≥20 %
• ≥50 %
• ≤212 HBW
• ≥30 J
• Annealed
• ≥600 MPa
• ≥360 MPa
• ≥20 %
• ≥50 %
• ≤212 HBW
• ≥30 J

• STATE
• Annealed
• RP
• ≥635 MPa
• YIELD
• ≥390 MPa
• EXTEND
• ≥20 %
• SHRINK
• ≥50 %
• HARDNESS
• ≤212 HBW
• IMPACT
• ≥30 J
• STATE
• Annealed
• RP
• ≥600 MPa
• YIELD
• ≥360 MPa
• EXTEND
• ≥20 %
• SHRINK
• ≥50 %
• HARDNESS
• ≤212 HBW
• IMPACT
• ≥30 J