ASTM A709/A709M Grade 345S Introduce
History
Smelting temperature:1567°C - 1226°C
Application:Structural steel for bridge
ASTM A709/A709M Grade 345S Material Chemical Composition
The chemical composition of the ASTM A709/A709M Grade 345S steel are as follows:
| Element | Min | Max |
|---|---|---|
| Copper (Cu) | - | 0.6000 |
| Aluminum (Al) | - | 0.1500 |
| Niobium (Nb) | - | 0.0500 |
| Vanadium (V) | - | 0.1100 |
| Nickel (Ni) | 0.4500 | - |
| Chromium (Cr) | - | 0.3500 |
| PhOsphorus (P) | - | 0.0350 |
| Sulfur (S) | - | 0.0450 |
| Manganese (Mn) | 0.5000 | 1.5000 |
| Silicon (Si) | - | 0.4000 |
| Carbon (C) | - | 0.2300 |
| (V+Nb) | - | 0.1500 |
| Vanadium (V) | - | 0.1500 |
| Nickel (Ni) | - | 0.4500 |
| Molybdenum (Mo) | - | 0.1500 |
| Manganese (Mn) | 0.5000 | 1.6000 |
| (CEV) | - | 0.4700 |
ASTM A709/A709M Grade 345S Material Mechanical Properties
Yield strength is the maximum stress which an object can withstand before it is no longer able to return to its original shape. ASTM A709/A709M Grade 345S steel has a high yield strength, ranging from 380MPa to 690MPa, depending on the grade and alloy combination. This allows the steel to withstand tremendous loads without permanently deforming or losing strength.
The mechanical properties of the ASTM A709/A709M Grade 345S steel are as follows:
| YieldRp0.2 | ≤ 741 (MPa) |
| TeileRm | ≤ 838 (MPa) |
| ImpactKV/Ku | 31(J) |
| ElongationA | 43% |
| Reduction in cross section on fractureZ | 34% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 344 |
ASTM A709/A709M Grade 345S Material Thermal Properties
The thermal performance parameters of the ASTM A709/A709M Grade 345S steel are as follows:
| Temperature (°C) | 31 | 265 | 251 |
| Modulus of elasticity (GPa) | - | 838 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 44 |
| Thermal conductivity (W/m·°C) | - | 34.3 | 33.2 |
| Specific thermal capacity (J/kg·°C) | - | 444 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.11 | - | - |
| Deity (kg/dm³) | - | - | 434 |
| Poisson’s coefficient, ν | - | - | 123 |