Gas nitriding is a thermo-chemical process of steel surface hardening. During gas nitriding, steel is heated to a temperature between 500 °C and 580 °C in the ammonia atmosphere. There is a layer of nitrides formed on the surface. By adding carbon to the workpiece surface, the process of nitrocarburizing is performed. Both processes can be upgraded with post-oxidation.
A solid compound layer (γ 'and / or ε- nitrides) is formed on the steel surface, followed by a diffusion layer and a tough core. The depth of nitriding layer (both compound and diffusion) ranges between 0.1 mm and 1.0 mm, and it depends on the duration of process, temperature and steel alloying elements.
GAS NITRIDING AND NITROCARBURIZING (VERTICAL)
Maximum workpiece dimensions | Maximum workpiece weight | Medium (surrounding substance) |
φ 1200 × 2000 | 2500 kg | NH₃+N₂+CO₂+H₂O |
Advantages:
- Hard nitriding layer provides high wear resistance, corrosion resistance and resistance to sliding friction,
- Dimensional changes in the process are minimal,
- Upgrading with post-oxidation provides a very good corrosion resistance,
- Partial nitriding is possible.
Applications:
- Parts for automotive industry,
- Tools for tool industry,
- Various machine parts (piston rods, spindles, cylinders, bushings, gears, etc.).