GB/T 699 U20103 Introduce
GB/T 699 U20103 is a popular alloy steel used for a variety of purposes, from precision machining to general engineering use. Its chemical composition includes iron, carbon, manganese, silicon, sulfur, and phosphorus. It also has a Brinell Hardness of approximately 180-240 HBW, and a tensile strength of 420-520MPa. The advantages of GB/T 699 U20103 steel include its high strength, hardness, and low cost. On the other hand, its disadvantages include limited ductility and brittleness over time. Common applications of GB/T 699 U20103 steel include automotive components, machine parts, engine components, and precision tools.
Smelting temperature:1144°C - 1856°C
Application:High quality carbon structural steel
GB/T 699 U20103 Material Chemical Composition
The chemical composition of the GB/T 699 U20103 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) | 0.3500 | 0.6500 |
| Copper (Cu) | - | 0.2000 |
| Chromium (Cr) | - | 0.1500 |
| Carbon (C) | 0.0700 | 0.1300 |
GB/T 699 U20103 Material Mechanical Properties
The mechanical properties of the GB/T 699 U20103 steel are as follows:
| YieldRp0.2 | ≤ 795 (MPa) |
| TeileRm | ≤ 777 (MPa) |
| ImpactKV/Ku | 14(J) |
| ElongationA | 33% |
| Reduction in cross section on fractureZ | 34% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 132 |
GB/T 699 U20103 Material Thermal Properties
The thermal performance parameters of the GB/T 699 U20103 steel are as follows:
| Temperature (°C) | 23 | 297 | 658 |
| Modulus of elasticity (GPa) | - | 794 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 11 |
| Thermal conductivity (W/m·°C) | - | 11.3 | 21.2 |
| Specific thermal capacity (J/kg·°C) | - | 344 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.21 | - | - |
| Deity (kg/dm³) | - | - | 333 |
| Poisson’s coefficient, ν | - | - | 431 |
GB/T 699 U20103 Material Machining Technology
Machining of GB/T 699 U20103 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 U20103 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 U20103 steel is used extensively in the manufacture of machinery and tools, as it is strong, durable and has excellent corrosion resistance.