ASTM A312/A312M Type 309H Introduce
ASTM A312/A312M is an international standard for seamless, welded, and heavily cold worked austenitic stainless steel pipes. It defines the chemical, mechanical, and metallurgical properties of the steel, along with the required physical and test results for standard pipes. The standard, which was first released in 2001, is published by the American Society for Testing and Materials (ASTM).
Smelting temperature:1261°C - 1276°C
Application:Seamless and welded austenitic stainless steel tube
ASTM A312/A312M Type 309H Material Chemical Composition
The chemical composition of the ASTM A312/A312M Type 309H steel are as follows:
| Element | Min | Max |
|---|---|---|
| Silicon (Si) | - | 1.0000 |
| Sulfur (S) | - | 0.0300 |
| PhOsphorus (P) | - | 0.0450 |
| Nickel (Ni) | 12.0000 | 15.0000 |
| Manganese (Mn) | - | 2.0000 |
| Chromium (Cr) | 22.0000 | 24.0000 |
| Carbon (C) | 0.0400 | 0.1000 |
ASTM A312/A312M Type 309H Material Mechanical Properties
The mechanical properties of ASTM A312/A312M Type 309H stainless steel pipe are essential in determining the strength, ductility, and toughness of the material. The three main mechanical properties of this material are its yield strength, tensile strength, and modulus of elasticity. The minimum required yield strength of these pipes is 0.2% of the specified ultimate tensile strength, the minimum required ultimate tensile strength is 65 Ksi (448 MPa), and the minimum required modulus of elasticity is 29,000 ksi (200,000 MPa).
The mechanical properties of the ASTM A312/A312M Type 309H steel are as follows:
| YieldRp0.2 | ≤ 682 (MPa) |
| TeileRm | ≤ 676 (MPa) |
| ImpactKV/Ku | 34(J) |
| ElongationA | 41% |
| Reduction in cross section on fractureZ | 22% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 333 |
ASTM A312/A312M Type 309H Material Thermal Properties
The thermal performance parameters of the ASTM A312/A312M Type 309H steel are as follows:
| Temperature (°C) | 22 | 192 | 715 |
| Modulus of elasticity (GPa) | - | 986 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 41 |
| Thermal conductivity (W/m·°C) | - | 32.3 | 41.2 |
| Specific thermal capacity (J/kg·°C) | - | 441 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.24 | - | - |
| Deity (kg/dm³) | - | - | 123 |
| Poisson’s coefficient, ν | - | - | 143 |
ASTM A312/A312M Type 309H Material Machining Technology
ASTM A312/A312M Type 309H is an austenitic stainless steel which contains a high level of chromium and nickel. This gives it excellent corrosion and heat resistance, making it an ideal choice for applications such as automotive exteriors, food processing and storage and other items exposed to high temperatures and moisture. It also has superior Machinability, making it well-suited for machining operations such as turning, drilling and grinding. Its mechanical properties are also high, including a yield strength of 80,000 PSI and a tensile strength of 105,000 PSI.