| AISI 4820 | |
 | |
| Category | Steel |
| Class | Alloy steel |
| Type | Standard |
| Common Names | Nickel-molybdenum steel |
| Designations | United States: ASTM A322 , ASTM A331 , ASTM A505 , ASTM A519 , ASTM A535 , SAE J404 , SAE J412 , SAE J770 , UNS G48200 |
| Composition | |
| |
| Element | Weight % |
| C | 0.18-0.23 |
| Mn | 0.50-0.70 |
| P | 0.035 (max) |
| S | 0.04 (max) |
| Si | 0.15-0.30 |
| Ni | 3.25-3.75 |
| Mo | 0.20-0.30 |
| Mechanical Properties | |
| |
| Properties | Conditions | ||
| T (°C) | Treatment | ||
| Density (×1000 kg/m3) | 7.7-8.03 | 25 | |
| Poisson's Ratio | 0.27-0.30 | 25 | |
| Elastic Modulus (GPa) | 190-210 | 25 | |
| Tensile Strength (Mpa) | 681.2 | 25 | annealed at 815°C more |
| Yield Strength (Mpa) | 464.0 | ||
| Elongation (%) | 22.3 | ||
| Reduction in Area (%) | 58.8 | ||
| Hardness (HB) | 197 | 25 | annealed at 815°C more |
| Impact Strength (J) (Izod) |
92.9 | 25 | annealed at 815°C more |
