Deep Cryogenic Treatment
Deep Cryogenic Treatment is an advanced metallurgical process used to enhance the mechanical and wear properties of ferrous and non-ferrous materials. In this process, components are gradually cooled down to extremely low temperatures (typically around -196°C) using liquid nitrogen and held for a controlled duration before being slowly brought back to room temperature.
This treatment transforms retained austenite into martensite and promotes the formation of fine carbide structures within the material. As a result, components achieve improved dimensional stability, higher hardness, increased wear resistance, and extended service life.
At NK Vacuum Heat Treatments, deep cryogenic treatment is carried out with controlled cooling and heating cycles to avoid thermal stresses and distortion. The process is suitable for a wide range of components including cutting tools, dies, moulds, automotive parts, gears, bearings, and precision components.
Why Gas Nitriding?
The formed hard layer imparts good wear resistance, fatigue strength, corrosive resistance & little or no dimensional change. Apart from this, the process contains specific advantages as listed below:
- Precise control of nitrogen by controlling the gas flow rate which gives all-round nitriding effect
- High dimensional stability & hardness, corrosion resistance & reduced coefficient friction
- Parts can be masked to prevent hardening in some areas.
- Large batch sizes are possible
Deep cryogenic treatment is suitable for tool steels, high speed steels (HSS), alloy steels, stainless steels, cast irons, carbides, and certain non-ferrous alloys. It is widely used for cutting tools, dies, moulds, gears, bearings, and wear components.
Deep cryogenic treatment does not directly increase hardness significantly, but it converts retained austenite into martensite and refines carbide structure. Typically, hardness improvement is 1–2 HRC, while greatly improving wear resistance and dimensional stability.
The complete process cycle generally takes 24 to 36 hours, including controlled cooling, soaking at around –196°C, and gradual return to room temperature.
The processing cost depends on material type, component size, weight, and the maximum number of parts that can be processed in a single batch. As each job has different requirements, pricing is determined accordingly. Please contact us for detailed pricing and technical discussion.
