| AISI 8640H | |
 | |
| Category | Steel |
| Class | Alloy steel |
| Type | H-steel |
| Common Names | Nickel-chromium-molybdenum steel |
| Designations |
Germany: DIN 1.6546 Italy: UNI 40 NiCrMo 2 KB United Kingdom: B.S. Type 7 United States: ASTM A304 , SAE J1268 , UNS H86400 |
| Composition | |
| |
| Element | Weight % |
| C | 0.37-0.44 |
| Mn | 0.70-1.05 |
| Cr | 0.35-0.65 |
| Ni | 0.35-0.75 |
| Mo | 0.15-0.25 |
| P | 0.035 |
| S | 0.040 |
| Si | 0.15-0.30 |
| 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) | 945 | 25 | cold drawn (round bar (25 mm)) more |
| Yield Strength (Mpa) | 931 | ||
| Elongation (%) | 9 | ||
| Reduction in Area (%) | 43 | ||
| Hardness (HB) | 277 | 25 | cold drawn (round bar (25 mm)) more |
