EN 10225 S355G15 + QT Introduce
EN 10225 is an European standard for hot rolled structural steel products that applies to steel sections (including wide flange beams), steel bars, wire rods, flat products (strip, plate, wide flats) and forgings that are manufactured for use in the offshore and related industries. EN 10225 S355G15 + QT specifies requirements for the manufacture of core components for offshore structures, including welded and fatigue performance criteria. It is also designed to provide weldable structural steels for use in the offshore industry, which have improved weldability when compared to traditional steels available.
Smelting temperature:1893°C - 1778°C
Application:Weldable structural steel with fixed offshore structure - Technical delivery conditions
EN 10225 S355G15 + QT Material Chemical Composition
The chemical composition of the EN 10225 S355G15 + QT steel are as follows:
| Element | Min | Max |
|---|---|---|
| Vanadium (V) | - | 0.1000 |
| Titanium (Ti) | - | 0.0200 |
| Tin (Sn) | - | 0.0200 |
| Silicon (Si) | 0.1500 | 0.5500 |
| Antimony (Sb) | - | 0.0100 |
| Sulfur (S) | - | 0.0070 |
| Lead (Pb) | - | 0.0100 |
| PhOsphorus (P) | - | 0.0250 |
| Nickel (Ni) | - | 0.3000 |
| (Nb+V) | - | 0.1000 |
| (Nb+Ti+V) | - | 0.1200 |
| Niobium (Nb) | - | 0.0500 |
| Nitrogen (N) | - | 0.0140 |
| Molybdenum (Mo) | - | 0.0800 |
| Manganese (Mn) | - | 1.6000 |
| Copper (Cu) | - | 0.3500 |
| (Cr+Ni+Cu+Mo) | - | 0.8000 |
| Chromium (Cr) | - | 0.2500 |
| Calcium (Ca) | - | 0.0050 |
| Carbon (C) | - | 0.1800 |
| Bismuth (Bi) | - | 0.0100 |
| Boron (B) | - | 0.0005 |
| Arsenic (As) | - | 0.0200 |
| Aluminum (Al) | - | 0.0600 |
EN 10225 S355G15 + QT Material Mechanical Properties
EN 10225 S355G15 + QT steel has a wide range of physical properties that make it an ideal material for many different uses. It has a relatively low density of approximately 7.68 g/cm3, which makes it an excellent option for applications where strength to weight ratio is important. The high chromium content of the alloy also gives it excellent corrosion resistance, making it a suitable material for use in corrosive environments. Another benefit of its composition is good formability, as the alloy tends to be malleable enough to cold form as well as heat treatable.
The mechanical properties of the EN 10225 S355G15 + QT steel are as follows:
| YieldRp0.2 | ≤ 159 (MPa) |
| TeileRm | ≤ 824 (MPa) |
| ImpactKV/Ku | 13(J) |
| ElongationA | 21% |
| Reduction in cross section on fractureZ | 21% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 122 |
EN 10225 S355G15 + QT Material Thermal Properties
The thermal performance parameters of the EN 10225 S355G15 + QT steel are as follows:
| Temperature (°C) | 24 | 913 | 394 |
| Modulus of elasticity (GPa) | - | 322 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 13 |
| Thermal conductivity (W/m·°C) | - | 44.3 | 22.2 |
| Specific thermal capacity (J/kg·°C) | - | 434 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.44 | - | - |
| Deity (kg/dm³) | - | - | 441 |
| Poisson’s coefficient, ν | - | - | 342 |
EN 10225 S355G15 + QT Material Machining Technology
EN 10225 S355G15 + QT steels are produced in grades S355G2+N, S355G3+N, S355G7+N, S355G8+N and S355G10+N. These grades are allocated according to specific strength levels so that appropriate application is possible. The grades are characterized by their minimum specified yield strength and weldability characteristics.