ASTM A508/A508M Grade 4N Class 2 Introduce
ASTM A508/A508M Grade 4N Class 2 is a kind of alloy steel and appears in ASTM International's (formerly American Society for Testing and Materials) specification. It is widely used in pressure vessel applications and is generally considered to be a general purpose alloy steel. It has a high strength to weight ratio and is able to possess both high tensile strength (ranging from 690MPa to 827 MPa) and yield strength (ranging from 414MPa to 655MPa) depending on its heat treatment. The steel is also highly capable of resisting abrasion and impact, making it perfect for applications requiring long-lasting performance.
Smelting temperature:1581°C - 1521°C
Application:Carbon steel and alloy steel forgings for quenching and tempering vacuum treatment of pressure vessels
ASTM A508/A508M Grade 4N Class 2 Material Chemical Composition
The chemical composition of the ASTM A508/A508M Grade 4N Class 2 steel are as follows:
| Element | Min | Max |
|---|---|---|
| Carbon (C) | - | 0.2300 |
| Manganese (Mn) | 0.2000 | 0.4000 |
| PhOsphorus (P) | - | 0.0200 |
| Sulfur (S) | - | 0.0200 |
| Silicon (Si) | - | 0.4000 |
| Nickel (Ni) | 2.8000 | 3.9000 |
| Chromium (Cr) | 1.5000 | 2.0000 |
| Molybdenum (Mo) | 0.4000 | 0.6000 |
| Copper (Cu) | - | 0.2500 |
| Vanadium (V) | - | 0.0300 |
| (Cb) | - | 0.0100 |
| Titanium (Ti) | - | 0.0150 |
| Calcium (Ca) | - | 0.0150 |
| Boron (B) | - | 0.0030 |
| Aluminum (Al) | - | 0.0250 |
| Silicon (Si) | - | 0.4000 |
| Aluminum (Al) | - | 0.0250 |
ASTM A508/A508M Grade 4N Class 2 Material Mechanical Properties
The mechanical properties of the ASTM A508/A508M Grade 4N Class 2 steel are as follows:
| YieldRp0.2 | ≤ 884 (MPa) |
| TeileRm | ≤ 278 (MPa) |
| ImpactKV/Ku | 21(J) |
| ElongationA | 32% |
| Reduction in cross section on fractureZ | 24% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 123 |
ASTM A508/A508M Grade 4N Class 2 Material Thermal Properties
The thermal performance parameters of the ASTM A508/A508M Grade 4N Class 2 steel are as follows:
| Temperature (°C) | 34 | 873 | 181 |
| Modulus of elasticity (GPa) | - | 358 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 21 |
| Thermal conductivity (W/m·°C) | - | 11.3 | 13.2 |
| Specific thermal capacity (J/kg·°C) | - | 424 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.42 | - | - |
| Deity (kg/dm³) | - | - | 413 |
| Poisson’s coefficient, ν | - | - | 122 |