ASTM A709/A709M A709 Grade 250 Introduce
The {stnadard} specification provides a minimum yield of 46,000 psi (320MPa) and a minimum tensile strength of 65,000 psi (450MPa) for the corresponding 250 grade. For a thickness up to 3.5" (89mm), the impact requirements can be met at room temperature.
Smelting temperature:1733°C - 1441°C
Application:Structural steel for bridge
ASTM A709/A709M A709 Grade 250 Material Chemical Composition
The chemical composition of the ASTM A709/A709M A709 Grade 250 steel are as follows:
| Element | Min | Max |
|---|---|---|
| Copper (Cu) | 0.2000 | - |
| PhOsphorus (P) | - | 0.0400 |
| Sulfur (S) | - | 0.0500 |
| Silicon (Si) | - | 0.4000 |
| Carbon (C) | - | 0.2500 |
| Silicon (Si) | - | 0.4000 |
| Manganese (Mn) | 0.8500 | 1.3500 |
| Copper (Cu) | 0.2000 | - |
| Carbon (C) | - | 0.2600 |
ASTM A709/A709M A709 Grade 250 Material Mechanical Properties
Tensile strength is a measure of the maximum load applied to an object before it deforms, breaks, or is otherwise mechanically stressed. ASTM A709/A709M A709 Grade 250 steel has an exceptional combination of high strength and ductility, allowing it to withstand heavy loads without fracturing or losing shape. The tensile strength of the steel ranges from 485MPa to 620MPa, depending on the grade and alloy combination.
The mechanical properties of the ASTM A709/A709M A709 Grade 250 steel are as follows:
| YieldRp0.2 | ≤ 875 (MPa) |
| TeileRm | ≤ 536 (MPa) |
| ImpactKV/Ku | 33(J) |
| ElongationA | 42% |
| Reduction in cross section on fractureZ | 13% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 322 |
ASTM A709/A709M A709 Grade 250 Material Thermal Properties
The thermal performance parameters of the ASTM A709/A709M A709 Grade 250 steel are as follows:
| Temperature (°C) | 33 | 776 | 494 |
| Modulus of elasticity (GPa) | - | 723 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 12 |
| Thermal conductivity (W/m·°C) | - | 23.3 | 11.2 |
| Specific thermal capacity (J/kg·°C) | - | 124 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.13 | - | - |
| Deity (kg/dm³) | - | - | 243 |
| Poisson’s coefficient, ν | - | - | 234 |