GB/T 20878 019Cr19Mo2NbTi Introduce
GB/T 20878 019Cr19Mo2NbTi stainless steel is a one-piece austenitic chromium-nickel alloy, usually used in applications that require high strength, corrosion and abrasion resistance. It contains chromium, nickel and molybdenum, as well as phosphorus and sulfur, which improve its mechanical properties and resistance to oxidation and corrosion. The addition of molybdenum stabilizes the austenitic structure and increases the alloy's resistance to pitting, crevice corrosion and general corrosion.
Smelting temperature:1261°C - 1898°C
Application:Stainless steel and heat resistant steel grades and chemical composition
GB/T 20878 019Cr19Mo2NbTi Material Chemical Composition
The chemical composition of the GB/T 20878 019Cr19Mo2NbTi steel are as follows:
| Element | Min | Max |
|---|---|---|
| (Ti+Nb) | 0.4400 | 0.8000 |
| Nitrogen (N) | - | 0.0350 |
| Molybdenum (Mo) | 1.7500 | 2.5000 |
| Chromium (Cr) | 17.5000 | 19.5000 |
| Nickel (Ni) | - | 1.0000 |
| Sulfur (S) | - | 0.0300 |
| PhOsphorus (P) | - | 0.0400 |
| Manganese (Mn) | - | 1.0000 |
| Silicon (Si) | - | 0.7500 |
| Carbon (C) | - | 0.0250 |
| PhOsphorus (P) | - | 0.0300 |
| Silicon (Si) | - | 1.0000 |
| (Ti+Nb) | - | 0.8000 |
| (Ti+Nb) | - | 0.8000 |
GB/T 20878 019Cr19Mo2NbTi Material Mechanical Properties
GB/T 20878 019Cr19Mo2NbTi 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 019Cr19Mo2NbTi steel are as follows:
| YieldRp0.2 | ≤ 258 (MPa) |
| TeileRm | ≤ 983 (MPa) |
| ImpactKV/Ku | 34(J) |
| ElongationA | 43% |
| Reduction in cross section on fractureZ | 31% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 332 |
GB/T 20878 019Cr19Mo2NbTi Material Thermal Properties
The thermal performance parameters of the GB/T 20878 019Cr19Mo2NbTi steel are as follows:
| Temperature (°C) | 11 | 176 | 364 |
| Modulus of elasticity (GPa) | - | 348 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 34 |
| Thermal conductivity (W/m·°C) | - | 33.3 | 34.2 |
| Specific thermal capacity (J/kg·°C) | - | 122 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.12 | - | - |
| Deity (kg/dm³) | - | - | 213 |
| Poisson’s coefficient, ν | - | - | 421 |
GB/T 20878 019Cr19Mo2NbTi Material Machining Technology
The machining of GB/T 20878 019Cr19Mo2NbTi steel requires specific cutting tools. A wide range of cutting tools such as drills, taps, reamers, and end mills can be used with this material. Drills are usually used to create the initial hole and are then followed by the tap. Reamers are often used to deburr and the finish off the hole. End mills are used to create more complicated shapes and profiles in the material.