ASTM A249/A249M S31008 Introduce
ASTM A249/A249M S31008 is an austenitic stainless steel specifically designed for use in boiler, superheater and heat exchanger tubes, which contain higher amounts of chromium and nickel compared to other stainless steels. This grade of steel is popular for its ability to resist corrosion and oxidation, and for its high strength-to-weight ratio. Due to its outstanding properties, it is ideal for a range of applications, such as pressure vessels, heat exchangers, and condensers.
Smelting temperature:1573°C - 1794°C
Application:Welded austenitic steel tubes for boilers, superheaters, heat exchangers and condensers
ASTM A249/A249M S31008 Material Chemical Composition
The chemical composition of the ASTM A249/A249M S31008 steel are as follows:
| Element | Min | Max |
|---|---|---|
| Silicon (Si) | - | 1.0000 |
| Sulfur (S) | - | 0.0300 |
| PhOsphorus (P) | - | 0.0450 |
| Nickel (Ni) | 19.0000 | 22.0000 |
| Manganese (Mn) | - | 2.0000 |
| Chromium (Cr) | 24.0000 | 26.0000 |
| Carbon (C) | - | 0.0800 |
ASTM A249/A249M S31008 Material Mechanical Properties
Elongation is a measure of the amount of elasticity that a material has when it reaches its yield strength. The elongation of ASTM A249/A249M S31008 steel ranges from 16% to 36%. The higher the elongation, the more elasticity and flexibility the steel has, allowing it to undergo greater loading before reaching its permanent deformation point.
The mechanical properties of the ASTM A249/A249M S31008 steel are as follows:
| YieldRp0.2 | ≤ 155 (MPa) |
| TeileRm | ≤ 395 (MPa) |
| ImpactKV/Ku | 43(J) |
| ElongationA | 43% |
| Reduction in cross section on fractureZ | 24% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 242 |
ASTM A249/A249M S31008 Material Thermal Properties
The thermal performance parameters of the ASTM A249/A249M S31008 steel are as follows:
| Temperature (°C) | 43 | 999 | 892 |
| Modulus of elasticity (GPa) | - | 872 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 43 |
| Thermal conductivity (W/m·°C) | - | 32.3 | 41.2 |
| Specific thermal capacity (J/kg·°C) | - | 141 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.32 | - | - |
| Deity (kg/dm³) | - | - | 243 |
| Poisson’s coefficient, ν | - | - | 231 |
ASTM A249/A249M S31008 Material Machining Technology
Machinability is a measure of how easily a material can be cut, drilled, or finished using machine tools. ASTM A249/A249M S31008 steel has a high machinability rating and can be easily cut, drilled, or finished using machine tools.