SAE J404 8645 Introduce
Steel is an important material in many industries, such as construction, transport, manufacturing, and aerospace. Since steel has different properties, there are a variety of steel grades available. Different steel grades have different mechanical, chemical, and physical properties. In order to ensure that the correct grade of steel is used for a given application, industry-standardized steel grades have been developed by the Society of Automobile Engineers (SAE). The SAE J404 steel standard is an industry-wide standard for automotive steels.
Smelting temperature:1396°C - 1168°C
Application:Chemical compositions of SAE alloy steels
SAE J404 8645 Material Chemical Composition
The chemical composition of the SAE J404 8645 steel are as follows:
| Element | Min | Max |
|---|---|---|
| Silicon (Si) | 0.1500 | 0.3500 |
| Sulfur (S) | - | 0.0400 |
| PhOsphorus (P) | - | 0.0350 |
| Nickel (Ni) | 0.4000 | 0.7000 |
| Molybdenum (Mo) | 0.1500 | 0.2500 |
| Manganese (Mn) | 0.7500 | 1.0000 |
| Chromium (Cr) | 0.4000 | 0.6000 |
| Carbon (C) | 0.4300 | 0.4800 |
| PhOsphorus (P) | - | 0.0300 |
| Sulfur (S) | - | 0.0400 |
| Lead (Pb) | 0.1500 | 0.3500 |
| PhOsphorus (P) | - | 0.0300 |
| Copper (Cu) | - | 0.3500 |
SAE J404 8645 Material Mechanical Properties
SAE J404 8645 steel also has excellent corrosion resistance. It is a low-alloy steel, so it has limited corrosion resistance compared to stainless steels. However, the addition of vanadium to the steel increases its corrosion resistance. This makes it an ideal choice for applications where corrosion resistance is an important factor, such as exposed elements or those in contact with sea water and other corrosive liquids.
The mechanical properties of the SAE J404 8645 steel are as follows:
| YieldRp0.2 | ≤ 865 (MPa) |
| TeileRm | ≤ 433 (MPa) |
| ImpactKV/Ku | 12(J) |
| ElongationA | 14% |
| Reduction in cross section on fractureZ | 22% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 412 |
SAE J404 8645 Material Thermal Properties
The thermal performance parameters of the SAE J404 8645 steel are as follows:
| Temperature (°C) | 32 | 477 | 524 |
| Modulus of elasticity (GPa) | - | 685 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 24 |
| Thermal conductivity (W/m·°C) | - | 34.3 | 12.2 |
| Specific thermal capacity (J/kg·°C) | - | 333 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.14 | - | - |
| Deity (kg/dm³) | - | - | 331 |
| Poisson’s coefficient, ν | - | - | 412 |
SAE J404 8645 Material Machining Technology
By taking the right steps when machining SAE J404 8645 steel, machinists can ensure successful results with minimal tool wear and downtime. The key considerations for safe and efficient machining of SAE J404 8645 steel include selecting the correct tooling and cutting parameters, using adequate lubricants and coolants, and employing simple techniques to minimize tool wear. With these tips in mind, machinists can look forward to achieving consistent, high-quality results when machining SAE J404 8645 steel.