GB/T 699 80-A Introduce
Steel is one of the most commonly used materials in the world. It is a strong and durable material that can be shaped in a variety of ways and is used in almost every industry. Steel comes in different grades, with each grade having different mechanical properties. GB/T 699 80-A steel is one of the most popular steels for mechanical applications in China.
Smelting temperature:1633°C - 1452°C
Application:High quality carbon structural steel
GB/T 699 80-A Material Chemical Composition
The chemical composition of the GB/T 699 80-A steel are as follows:
| Element | Min | Max |
|---|---|---|
| Copper (Cu) | - | 0.2500 |
| Nickel (Ni) | - | 0.3000 |
| Chromium (Cr) | - | 0.2500 |
| Sulfur (S) | - | 0.0300 |
| PhOsphorus (P) | - | 0.0300 |
| Manganese (Mn) | 0.7000 | 1.0000 |
| Silicon (Si) | 0.1700 | 0.3700 |
| Carbon (C) | 0.7700 | 0.8500 |
GB/T 699 80-A Material Mechanical Properties
The mechanical properties of the GB/T 699 80-A steel are as follows:
| YieldRp0.2 | ≤ 691 (MPa) |
| TeileRm | ≤ 771 (MPa) |
| ImpactKV/Ku | 24(J) |
| ElongationA | 12% |
| Reduction in cross section on fractureZ | 32% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 434 |
GB/T 699 80-A Material Thermal Properties
The thermal performance parameters of the GB/T 699 80-A steel are as follows:
| Temperature (°C) | 22 | 614 | 111 |
| Modulus of elasticity (GPa) | - | 637 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 12 |
| Thermal conductivity (W/m·°C) | - | 43.3 | 43.2 |
| Specific thermal capacity (J/kg·°C) | - | 114 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.12 | - | - |
| Deity (kg/dm³) | - | - | 131 |
| Poisson’s coefficient, ν | - | - | 413 |
GB/T 699 80-A Material Machining Technology
Machining of GB/T 699 80-A steel requires a combination of multiple processes, such as turning, drilling, grinding, and welding. Heat treatment is also used to alter the physical and chemical properties of the steel. Each process offers advantages for specific components, and knowing which process is best for the job is essential for ensuring quality results.