AISI 4320 | |
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Category | Steel |
Class | Alloy steel |
Type | Standard |
Common Names | Nickel-chromium-molybdenum steel |
Designations | United States: ASTM A322 , ASTM A331 , ASTM A505 , ASTM A519 , ASTM A535 , SAE J404 , SAE J412 , SAE J770 , UNS G43200 |


Composition | |
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Element | Weight % |
C | 0.17-0.22 |
Mn | 0.45-0.65 |
P | 0.035 (max) |
S | 0.04 (max) |
Si | 0.15-0.30 |
Cr | 0.40-0.60 |
Ni | 1.65-2.00 |
Mo | 0.20-0.30 |


Mechanical Properties | |
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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) | 579.2 | 25 | annealed at 850°C more |
Yield Strength (Mpa) | 609.5 | ||
Elongation (%) | 29.0 | ||
Reduction in Area (%) | 58.4 | ||
Hardness (HB) | 163 | 25 | annealed at 850°C more |
Impact Strength (J) (Izod) |
109.8 | 25 | annealed at 850°C more |

