SAE J404 AISI 4320 Introduce
SAE J404 (Steel, Carbon and High-Strength, Low Alloy – Chemical Composition Limits) is a standard created by the Society of Automotive Engineers (SAE) that outlines the limits for chemical composition of carbon and alloy steel. This standard is used as a reference for specifying automotive steel grades that are produced for various applications, especially for use in parts like engine blocks and crankshafts.
Smelting temperature:1616°C - 1486°C
Application:Chemical compositions of SAE alloy steels
SAE J404 AISI 4320 Material Chemical Composition
The chemical composition of the SAE J404 AISI 4320 steel are as follows:
| Element | Min | Max |
|---|---|---|
| Carbon (C) | 0.1700 | 0.2200 |
| Manganese (Mn) | 0.4500 | 0.6500 |
| PhOsphorus (P) | - | 0.0350 |
| Sulfur (S) | - | 0.0400 |
| Silicon (Si) | 0.1500 | 0.3500 |
| Nickel (Ni) | 1.6500 | 2.0000 |
| Chromium (Cr) | 0.4000 | 0.6000 |
| Molybdenum (Mo) | 0.2000 | 0.3000 |
| Copper (Cu) | - | 0.3500 |
| PhOsphorus (P) | - | 0.0250 |
| Sulfur (S) | - | 0.0250 |
| Silicon (Si) | 0.1500 | 0.3000 |
| Silicon (Si) | 0.1500 | 0.3000 |
SAE J404 AISI 4320 Material Mechanical Properties
SAE J404 AISI 4320 steel has good strength and hardness. It has a hardness range of 166 to 287 Brinell, a tensile strength range of 890 to 1340 MPa, a yield strength range of 870 to 1240 MPa, and an ultimate tensile strength range of 1040 to 1450 MPa. It has an elongation rate of 16 to 20 percent in 50 mm and a Poisson's ratio range of 0.26 to 0.30. SAE J 404 steel also has good toughness and ductility and can be easily machined and formed.
The mechanical properties of the SAE J404 AISI 4320 steel are as follows:
| YieldRp0.2 | ≤ 739 (MPa) |
| TeileRm | ≤ 825 (MPa) |
| ImpactKV/Ku | 12(J) |
| ElongationA | 41% |
| Reduction in cross section on fractureZ | 11% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 434 |
SAE J404 AISI 4320 Material Thermal Properties
The thermal performance parameters of the SAE J404 AISI 4320 steel are as follows:
| Temperature (°C) | 32 | 173 | 787 |
| Modulus of elasticity (GPa) | - | 431 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 33 |
| Thermal conductivity (W/m·°C) | - | 13.3 | 12.2 |
| Specific thermal capacity (J/kg·°C) | - | 343 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.32 | - | - |
| Deity (kg/dm³) | - | - | 414 |
| Poisson’s coefficient, ν | - | - | 443 |
SAE J404 AISI 4320 Material Machining Technology
SAE J404 AISI 4320 steel is an important engineering material with many excellent properties, making it a preferred choice for many machining and fabrication applications. However, machining SAE J404 AISI 4320 steel presents a number of challenges due to its combination of high hardness, strength and ductility.