Technology of the nitrocarburizing in molten salt baths
Summary of the most important features and advantages
- increases surface hardness,
- strengthens fatigue strength, resistance to abrasion and seizure as well as anti-adhesive properties,
- enhances corrosion resistance,
- improves the visual aspects (anthracite or black product color).
- Surface preparation – washing the surfaces of details in water and alkaline baths in order to remove substances remaining after mechanical treatment (surfaces contaminated with oils, emulsions, and anti-corrosion agents) – the branch should be informed about the type of treatment and the chemical substances which have been used in order to select the appropriate washing technology. The packaging must correspond to the delivery condition and be completely leakproof. The goods are returned in their Owner’s packaging in the condition as for delivery.
- Nitrocarburizing (SURSULF®) – increases surface hardness and improves tribological properties. We carry out processes at temperatures ranging between 530 – 600oC. In the case of heat-treated parts, the tempering temperatures should be taken into account – the nitrocarburizing process is also secondary tempering and may lead to a reduction in the hardness of the hardened layer (or the entire product). Nitrocarburizing can be also used on the previously carburized layers for further improvement of the surface properties.
- Passivation (OXYNIT®) – increases corrosion resistance and gives an attractive appearance. Used individually it corresponds to high-quality blackening.
- Impregnation in COROLAC® environments under various conditions – it is a permanent anti-corrosion protection in difficult operating conditions (parts of construction machinery, rail transport, working in brine and other difficult chemical environments under conditions of increased friction).
- Nitrocarburizing (TF-N® – formerly TF-1) – increases surface hardness, gives increased tribological properties. It is used on details with the required low roughness and limited and predictable geometric deformations.
- microblasting – surface polishing with micro-size cast steel shots,
- vibro-abrasive machining,
- drying in ecological agents (walnut shells, maize abrasive, etc.).
Standard parts with dimensions not exceeding Ømax 800 mm and length up to 1800 mm for a load of up to 600 kg gross weight
Pipelines, diffusers and other products length up to 25 m and Ø max 800 mm in diameter requiring nitriding of a limited area
- subjects to increased wear under friction conditions,
- working in harsh environmental conditions (moisture, chemicals),
- susceptible to geometric deformation during high-temperature heat treatment,
- expensive due to the fact that they are made of high-alloy steels (the possibility of replacing them with cheaper steels + carrying out the nitrocarburizing treatment),
- requiring durable surface coatings (nitrocarburization is an excellent base layer for other surface treatments),
- requiring durable layers with a stable surface structure (e.g. for optical products or permanently attractive visually),
- requiring special accompanying properties (e.g. magnetic).
- environmentally friendly.
- Q – full process of nitrocarburizing in the TENIFER® technology,
- P – mid-operational micropolishing of the surfaces,
- Q – shortened re-nitrocarburizing with full passivation and post-treatment.
- increased fatigue strength,
- increased wear resistance by friction,
- very high corrosion resistance.
- Q – Quenching – means the complete process of nitrocarburizing and passivation (blackening) and “freezing” of the surface condition.
- P – Polishing – specialized mechanical treatment of the finished product in order to obtain a high-quality final surface with low roughness.
- Q – Quenching – enhancing the expected mechanical and physico-chemical properties of the surface layer on a superfinished polished surface.
process by multiplying the advantages of nitrocarburizing.