ASTM A790/A790M S81921 Introduce
The general chemical composition of ASTM A790/A790M S81921 duplex stainless steel includes a minimum of 18-20% chromium, 3-4% nickel, and a maximum of 0.15-0.22% carbon. Other alloying elements may include molybdenum, manganese, silicon and nitrogen, depending on the alloy grade. The mechanical and physical properties of ASTM A790/A790M S81921 depend on the grades of duplex stainless steel. Grade 2205 is one of the most common grades in this classification and provides superior corrosion resistance, strength and fabrication characteristics.
Smelting temperature:1696°C - 1335°C
Application:Seamless and welded ferritic/austenitic stainless steel tube
ASTM A790/A790M S81921 Material Mechanical Properties
ASTM A790/A790M S81921 is a special type of austenitic duplex stainless steel with a combination of properties that make it useful for many different applications. The alloy contains a balance of chromium and nickel, as well as small amounts of molybdenum, nitrogen, and other elements. This combination of elements gives it excellent weldability, corrosion resistance, thermal properties, and mechanical properties, making it suitable for many different applications.
The mechanical properties of the ASTM A790/A790M S81921 steel are as follows:
| YieldRp0.2 | ≤ 285 (MPa) |
| TeileRm | ≤ 583 (MPa) |
| ImpactKV/Ku | 22(J) |
| ElongationA | 24% |
| Reduction in cross section on fractureZ | 42% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 131 |
ASTM A790/A790M S81921 Material Thermal Properties
The thermal performance parameters of the ASTM A790/A790M S81921 steel are as follows:
| Temperature (°C) | 32 | 224 | 758 |
| Modulus of elasticity (GPa) | - | 444 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 22 |
| Thermal conductivity (W/m·°C) | - | 22.3 | 44.2 |
| Specific thermal capacity (J/kg·°C) | - | 444 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.23 | - | - |
| Deity (kg/dm³) | - | - | 223 |
| Poisson’s coefficient, ν | - | - | 424 |
ASTM A790/A790M S81921 Material Machining Technology
The use of coolants can be beneficial when machining ASTM A790/A790M S81921 steel. Coolants help to reduce the tool wear by keeping the heat generated during the machining process under control. Additionally, the use of a coolant will reduce the time required for the machining process and increase overall accuracy and precision. A water-based coolant is usually recommended, as it will reduce the risk of fire when machining and also extend the life of the cutting tools.