GB/T 699 U20303 Introduce
Steel is one of the most widely used materials in the world, used for a variety of applications from construction to transportation. GB/T 699 U20303 is a popular alloy steel used for a variety of purposes, from precision machining to general engineering use. GB/T 699 U20303 is an alloy which is made up of two different types of steel: high-carbon steel and low-carbon steel. The high-carbon steel is used for the formation of the "matrix" of the metal; this contains the majority of the chemical elements listed above. The low-carbon steel is added for strength and is found mainly in the "alloying" elements. This combination of high-carbon and low-carbon steel creates a metal that is stronger and more durable than either type of steel alone.
Smelting temperature:1689°C - 1311°C
Application:High quality carbon structural steel
GB/T 699 U20303 Material Chemical Composition
The chemical composition of the GB/T 699 U20303 steel are as follows:
| Element | Min | Max |
|---|---|---|
| Silicon (Si) | 0.1700 | 0.3700 |
| Sulfur (S) | - | 0.0300 |
| PhOsphorus (P) | - | 0.0300 |
| Nickel (Ni) | - | 0.3000 |
| Manganese (Mn) | 0.5000 | 0.8000 |
| Copper (Cu) | - | 0.2500 |
| Chromium (Cr) | - | 0.2500 |
| Carbon (C) | 0.2700 | 0.3400 |
GB/T 699 U20303 Material Mechanical Properties
The mechanical properties of the GB/T 699 U20303 steel are as follows:
| YieldRp0.2 | ≤ 253 (MPa) |
| TeileRm | ≤ 261 (MPa) |
| ImpactKV/Ku | 34(J) |
| ElongationA | 23% |
| Reduction in cross section on fractureZ | 24% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 133 |
GB/T 699 U20303 Material Thermal Properties
The thermal performance parameters of the GB/T 699 U20303 steel are as follows:
| Temperature (°C) | 33 | 653 | 455 |
| Modulus of elasticity (GPa) | - | 616 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 13 |
| Thermal conductivity (W/m·°C) | - | 21.3 | 11.2 |
| Specific thermal capacity (J/kg·°C) | - | 113 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.21 | - | - |
| Deity (kg/dm³) | - | - | 312 |
| Poisson’s coefficient, ν | - | - | 224 |
GB/T 699 U20303 Material Machining Technology
Machining of GB/T 699 U20303 steel typically requires a combination of diverse machining processes for quality production of more complex components. China being the biggest steel producers in the world, manufactures and supplies GB/T 699 U20303 steel, which is a high-quality carbon structural steel. This type of steel is machinable and is suitable for the manufacture of automotive parts, machine tools, and many other machines. Typically, GB/T 699 U20303 steel is used extensively in the manufacture of machinery and tools, as it is strong, durable and has excellent corrosion resistance.