GB/T 1591 Q390B Introduce
Steel is an essential material in construction and engineering, and it is important to have a common understanding of how different steel grades are used. The Chinese government set the standard for steel classification in China with the introduction of the GB/T 1591 steel standard. This standard is designed to improve the industrialization of steel and safeguard China's economic and environmental interests.
Smelting temperature:1251°C - 1827°C
Application:Low alloy high strength structural steel
GB/T 1591 Q390B Material Chemical Composition
The chemical composition of the GB/T 1591 Q390B steel are as follows:
| Element | Min | Max |
|---|---|---|
| Carbon (C) | - | 0.2000 |
| Silicon (Si) | - | 0.5000 |
| Manganese (Mn) | - | 1.7000 |
| PhOsphorus (P) | - | 0.0350 |
| Sulfur (S) | - | 0.0350 |
| Niobium (Nb) | - | 0.0700 |
| Vanadium (V) | - | 0.2000 |
| Titanium (Ti) | - | 0.2000 |
| Chromium (Cr) | - | 0.3000 |
| Nickel (Ni) | - | 0.5000 |
| Copper (Cu) | - | 0.3000 |
| Nitrogen (N) | - | 0.0150 |
| Molybdenum (Mo) | - | 0.1000 |
GB/T 1591 Q390B Material Mechanical Properties
Fatigue strength is the measure of a material's ability to resist cyclic loading. GB/T 1591 Q390B steels are typically evaluated for their fatigue strength by performing tests on Weibull specimens. These tests measure the maximum stress that can be applied without failure.
The mechanical properties of the GB/T 1591 Q390B steel are as follows:
| YieldRp0.2 | ≤ 135 (MPa) |
| TeileRm | ≤ 644 (MPa) |
| ImpactKV/Ku | 21(J) |
| ElongationA | 24% |
| Reduction in cross section on fractureZ | 14% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 322 |
GB/T 1591 Q390B Material Thermal Properties
The thermal performance parameters of the GB/T 1591 Q390B steel are as follows:
| Temperature (°C) | 22 | 869 | 446 |
| Modulus of elasticity (GPa) | - | 429 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 31 |
| Thermal conductivity (W/m·°C) | - | 32.3 | 31.2 |
| Specific thermal capacity (J/kg·°C) | - | 123 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.22 | - | - |
| Deity (kg/dm³) | - | - | 331 |
| Poisson’s coefficient, ν | - | - | 124 |
GB/T 1591 Q390B Material Machining Technology
GB/T 1591 Q390B has been widely used in the construction industry and has been used in various large-scale projects. The high tensile strength and yield strength of GB/T 1591 Q390Bs are higher than that of conventional carbon steels. The low alloy and high strength of GB/T 1591 Q390Bs can reduce the weight and extend the life of structures and reduce the cost of use. At the same time, the excellent properties of GB/T 1591 Q390B can make cars and containers lighter, which is beneficial for fuel saving and environmental protection.