GB/T 20878 05Cr17Ni4Cu4Nb Introduce
GB/T 20878 05Cr17Ni4Cu4Nb is a grade of hardened steel with a wide variety of applications in the engineering and fabrication industry. Its thermal properties make it an excellent choice in applications that require heat resistance, dimensional accuracy, and strength. Thanks to its versatility, this hardened steel is an excellent choice for a wide variety of projects.
Smelting temperature:1839°C - 1668°C
Application:Stainless steel and heat resistant steel grades and chemical composition
GB/T 20878 05Cr17Ni4Cu4Nb Material Chemical Composition
The chemical composition of the GB/T 20878 05Cr17Ni4Cu4Nb steel are as follows:
| Element | Min | Max |
|---|---|---|
| (Nb+Ta) | 0.1500 | 0.3500 |
| Nitrogen (N) | - | 0.0500 |
| Titanium (Ti) | - | 0.0500 |
| Aluminum (Al) | - | 0.0500 |
| Copper (Cu) | 3.0000 | 3.7000 |
| Chromium (Cr) | 15.0000 | 16.0000 |
| Nickel (Ni) | 3.8000 | 4.5000 |
| Sulfur (S) | - | 0.0200 |
| PhOsphorus (P) | - | 0.0300 |
| Manganese (Mn) | - | 0.5000 |
| Silicon (Si) | - | 1.0000 |
| Carbon (C) | - | 0.0550 |
| Sulfur (S) | - | 0.0300 |
| PhOsphorus (P) | - | 0.0400 |
| Nickel (Ni) | 3.0000 | 5.0000 |
| Niobium (Nb) | 0.1500 | 0.4500 |
| Manganese (Mn) | - | 1.0000 |
| Copper (Cu) | 3.0000 | 5.0000 |
| Chromium (Cr) | 15.0000 | 17.5000 |
| Carbon (C) | - | 0.0700 |
GB/T 20878 05Cr17Ni4Cu4Nb Material Mechanical Properties
GB/T 20878 05Cr17Ni4Cu4Nb steel has superior mechanical properties compared to ordinary steel. It has an excellent strength-to-weight ratio and good levels of stiffness, ductility, and machinability. Its mechanical properties are largely dependent on the grade, with higher grades having higher strength and lower ductility.
The mechanical properties of the GB/T 20878 05Cr17Ni4Cu4Nb steel are as follows:
| YieldRp0.2 | ≤ 412 (MPa) |
| TeileRm | ≤ 467 (MPa) |
| ImpactKV/Ku | 21(J) |
| ElongationA | 33% |
| Reduction in cross section on fractureZ | 43% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 332 |
GB/T 20878 05Cr17Ni4Cu4Nb Material Thermal Properties
The thermal performance parameters of the GB/T 20878 05Cr17Ni4Cu4Nb steel are as follows:
| Temperature (°C) | 14 | 242 | 382 |
| Modulus of elasticity (GPa) | - | 414 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 22 |
| Thermal conductivity (W/m·°C) | - | 11.3 | 24.2 |
| Specific thermal capacity (J/kg·°C) | - | 211 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.31 | - | - |
| Deity (kg/dm³) | - | - | 321 |
| Poisson’s coefficient, ν | - | - | 321 |
GB/T 20878 05Cr17Ni4Cu4Nb Material Machining Technology
The type of cutting tool chosen depends on the end-use application and the desired cutting performance. In general, high-speed steel (HSS) or high-speed cobalt (HSC) tools are best for machining GB/T 20878 05Cr17Ni4Cu4Nb steel as they have excellent cutting properties and can cope with high cutting speeds and feeds. Carbide grade tools may be used for high-shear or high-feed applications.