Introduction to the principle and function of deep cooling process

The so-called deep cooling process is to use liquid nitrogen (-196℃) as a cooling medium to continue the cooling process of the quenched metal material to a temperature far below room temperature, so as to further transform the residual austenite existing after conventional heat treatment, thereby improving the performance of the metal material. Cryogenic treatment can significantly improve the wear resistance, toughness and dimensional stability of metal workpieces, and increase the service life of the workpiece exponentially.

In industry, the treatment method of further cooling the material after ordinary heat treatment to -100℃～-196℃ is called cryogenic treatment. It can reduce the residual austenite content, promote the precipitation of fine carbides, reduce intergranular tensile stress, and thus improve the performance of steel:

What are the effects of deep cooling process?

1. It can transform residual austenite, improve the hardness and wear resistance of the workpiece, and stabilize the size of the workpiece;

2. It can precipitate ultrafine carbides to improve the wear resistance of the workpiece; it can refine the grains and improve the impact toughness of the workpiece;

3. It can multiply the corrosion resistance of martensitic stainless steel and improve the polishing performance of the workpiece;

4. It can improve the conductivity and corrosion resistance of non-ferrous metals;

5. It can reduce mold deformation and cracking. Improve the dimensional accuracy of the workpiece.

What are the advantages of deep cooling process?

1. It transforms the residual austenite with lower hardness into harder, more stable, more wear-resistant and heat-resistant martensite;

2. The grain boundaries, grain boundary edges and grain boundary interiors of martensite are decomposed and refined, and a large number of ultrafine carbides are precipitated. The supersaturated martensite improves the toughness of the material in the deep cooling process, with high impact toughness, improved matrix tempering stability and fatigue resistance; improved wear resistance; improved dimensional stability. Thus, the purpose of strengthening the matrix, improving the quality of heat treatment, reducing the number of tempering, and extending the life of the mold is achieved;

3. After deep cooling process, the internal thermal stress and mechanical stress of the material are greatly reduced, and because the micropores or stress concentration parts produce plastic rheology during the cooling process, compressive stress will be generated on the surface of such vacancies during the heating process. This compressive stress can greatly reduce the damage of defects to the local performance of the workpiece, thereby effectively reducing the possibility of deformation and cracking of metal workpieces.

Deep cooling equipment