ASTM A249/A249M Type 304N Introduce
ASTM A249/A249M Type 304N steel is an austenitic stainless steel specifically designed for use in boiler, superheater, and heat exchanger tubes. Its high chromium and nickel content make it highly resistant to corrosion and oxidation, and its high strength-to-weight ratio makes it suitable for a range of applications. Furthermore, the steel offers improved heat resistance and good weldability, making it ideal for operations involving higher temperatures.
Smelting temperature:1353°C - 1224°C
Application:Welded austenitic steel tubes for boilers, superheaters, heat exchangers and condensers
ASTM A249/A249M Type 304N Material Chemical Composition
The chemical composition of the ASTM A249/A249M Type 304N steel are as follows:
| Element | Min | Max |
|---|---|---|
| Silicon (Si) | - | 1.0000 |
| Sulfur (S) | - | 0.0300 |
| PhOsphorus (P) | - | 0.0450 |
| Nickel (Ni) | 8.0000 | 11.0000 |
| Nitrogen (N) | 0.1000 | 0.1600 |
| Manganese (Mn) | - | 2.0000 |
| Chromium (Cr) | 18.0000 | 20.0000 |
| Carbon (C) | - | 0.0800 |
ASTM A249/A249M Type 304N Material Mechanical Properties
ASTM A249/A249M Type 304N steel is an incredibly versatile and capable alloy with numerous mechanical properties that make it an ideal choice for many applications across various industries. From its remarkable tensile strength and yield strength to its excellent weldability, machinability, and corrosion resistance, ASTM A249/A249M Type 304N steel is an incredibly reliable and trusted material.
The mechanical properties of the ASTM A249/A249M Type 304N steel are as follows:
| YieldRp0.2 | ≤ 492 (MPa) |
| TeileRm | ≤ 482 (MPa) |
| ImpactKV/Ku | 43(J) |
| ElongationA | 11% |
| Reduction in cross section on fractureZ | 32% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 442 |
ASTM A249/A249M Type 304N Material Thermal Properties
The thermal performance parameters of the ASTM A249/A249M Type 304N steel are as follows:
| Temperature (°C) | 22 | 576 | 358 |
| Modulus of elasticity (GPa) | - | 697 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 44 |
| Thermal conductivity (W/m·°C) | - | 44.3 | 22.2 |
| Specific thermal capacity (J/kg·°C) | - | 241 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.42 | - | - |
| Deity (kg/dm³) | - | - | 223 |
| Poisson’s coefficient, ν | - | - | 111 |
ASTM A249/A249M Type 304N Material Machining Technology
There are several methods for machining ASTM A249/A249M Type 304N steel. It can be machined using traditional methods such as drilling, tapping, reaming, milling, and turning. It can also be machined using specialized techniques such as electrochemical machining and laser machining. When it comes to high-precision machining, electrochemical machining is the preferred method as it is capable of producing intricate components with extremely tight tolerances. With laser machining, components can be produced with increased accuracy and reduced lead time.