AISI 8622 Round Bar (UNS G86220)
AISI 8622 Round Bar is a nickel–chromium–molybdenum (Ni-Cr-Mo) alloy steel primarily used for carburizing and case-hardening applications. Compared to AISI 8620, this grade contains slightly higher carbon, offering better hardenability and higher core strength after heat treatment. It is ideal for precision components requiring a hard, wear-resistant surface with a tough core.
Key Features
- Low-carbon Ni-Cr-Mo alloy steel for case hardening
- Excellent carburizing response
- High surface hardness with tough and ductile core
- Improved strength over AISI 8620
- Good machinability in annealed condition
Equivalent Grades
| Standard |
Equivalent / Closest Grade |
| EN |
20NiCrMo2-2 |
| DIN |
1.6523 |
| JIS |
SNCM220 |
| IS |
20NiCrMo2 |
Sizes
- Diameter: 12 mm to 600 mm
- Length: 3 m, 6 m, or cut-to-length
- Custom sizes available
Chemical Composition
| Element |
% |
| Carbon (C) |
0.20 – 0.25 |
| Nickel (Ni) |
0.40 – 0.70 |
| Chromium (Cr) |
0.40 – 0.60 |
| Molybdenum (Mo) |
0.15 – 0.25 |
| Manganese (Mn) |
0.70 – 0.90 |
| Silicon (Si) |
0.15 – 0.35 |
| Phosphorus (P) |
≤ 0.035 |
| Sulfur (S) |
≤ 0.040 |
| Iron (Fe) |
Balance |
Mechanical Properties
| Property |
Value |
| Core Tensile Strength |
850 – 1050 MPa |
| Yield Strength |
600 – 750 MPa |
| Elongation |
14 – 18% |
| Surface Hardness |
58 – 62 HRC |
| Core Hardness |
30 – 36 HRC |
Physical Properties
| Property |
Value |
| Density |
7.85 g/cm³ |
| Melting Point |
~1415°C |
| Thermal Conductivity |
≈ 42.5 W/m·K |
| Specific Heat Capacity |
≈ 460 J/kg·K |
| Modulus of Elasticity |
≈ 205 GPa |
| Electrical Resistivity |
≈ 0.20 µΩ·m |
| Coefficient of Thermal Expansion |
≈ 11.5 × 10⁻⁶ /°C (20–100°C) |
Types of AISI 8622 Round Bar
- Hot Rolled Round Bar
- Forged Round Bar
- Annealed Round Bar
- Peeled Round Bar
- Turned & Polished Round Bar
- Carburized & Heat Treated Round Bar
- Cut-to-Length Round Bar
Applications
- Gears and pinions
- Transmission & gearbox parts
- Differential gears
- Automotive and tractor components
- Heavy engineering machinery parts
Reviews
There are no reviews yet.