ASTM A573/A573M A573 Grade 450 Introduce
The ASTM A573/A573M A573 Grade 450 standard is relatively new, having been developed in 2021, but is quickly becoming the industry standard for the design, fabrication and use of structural steel plates. It offers improved reliability, cost-effectiveness, traceability and uniform requirements over the A573/A576 standard it replaced and is the result of an effort by an international industry group to ensure the quality of steel plates. By providing a single, uniform standard of care and quality, the ASTM A573/A573M A573 Grade 450 specification ensures that steel plates created to its standard are of the highest quality for their intended use.
Smelting temperature:1872°C - 1195°C
Application:Structural carbon steel plate for enhancing toughness
ASTM A573/A573M A573 Grade 450 Material Chemical Composition
The chemical composition of the ASTM A573/A573M A573 Grade 450 steel are as follows:
| Element | Min | Max |
|---|---|---|
| Carbon (C) | - | 0.2400 |
| Manganese (Mn) | 0.8500 | 1.2000 |
| PhOsphorus (P) | - | 0.0300 |
| Sulfur (S) | - | 0.0300 |
| Silicon (Si) | 0.1500 | 0.4000 |
| Sulfur (S) | - | 0.0400 |
| PhOsphorus (P) | - | 0.0350 |
ASTM A573/A573M A573 Grade 450 Material Mechanical Properties
The chemical composition of ASTM A573/A573M A573 Grade 450 is composed of carbon (C), manganese (Mn), phosphorous (P), sulfur (S), and silicon (Si). It has a moderate carbon content of 0.27 to 0.33%. This can be beneficial for various mechanical applications, as it offers good strength when exposed to an elevated temperature and pressure. The manganese content of ASTM A573/A573M A573 Grade 450 ranges from 1.70-2.00%, providing excellent wear and corrosion resistance. Phosphorous and sulfur are both included up to a maximum content of 0.050%, which helps to prevent cracking due to embrittlement. Silicon is also added up to a maximum of 0.20%, and acts as an additional strengthening agent in this alloy.
The mechanical properties of the ASTM A573/A573M A573 Grade 450 steel are as follows:
| YieldRp0.2 | ≤ 151 (MPa) |
| TeileRm | ≤ 263 (MPa) |
| ImpactKV/Ku | 14(J) |
| ElongationA | 24% |
| Reduction in cross section on fractureZ | 11% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 244 |
ASTM A573/A573M A573 Grade 450 Material Thermal Properties
The thermal performance parameters of the ASTM A573/A573M A573 Grade 450 steel are as follows:
| Temperature (°C) | 34 | 614 | 319 |
| Modulus of elasticity (GPa) | - | 532 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 21 |
| Thermal conductivity (W/m·°C) | - | 12.3 | 12.2 |
| Specific thermal capacity (J/kg·°C) | - | 113 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.44 | - | - |
| Deity (kg/dm³) | - | - | 311 |
| Poisson’s coefficient, ν | - | - | 342 |
ASTM A573/A573M A573 Grade 450 Material Machining Technology
Turning: This process is used to produce cylindrical components from ASTM A573/A573M A573 Grade 450 steel. It is generally done with a lathe machine, which rotates the component at high speeds and a cutting tool removes the material from the component. The cutting tool is usually made from hardened steel, HSS, tungsten carbide, or ceramics. It is important to choose the correct grade of cutting tool for the component being machined as this will significantly affect the quality of the finished product.