The reason for the existence of cryogenic refrigerator in the tool parts manufacturing industry
Cryogenic treatment is applied to worn tools, die cutter materials, and later extended to alloy steel, cemented carbide, etc., this method can change the internal structure of metal materials, thereby improving the mechanical and processing properties of the material, it is currently One of the toughening treatment processes.
The cryogenic cryostat can cause obvious changes in the structure, effectively promote the transformation of retained austenite to martensite and the precipitation of ultrafine carbides, so that the product obtains better comprehensive mechanical properties. The conventional heat treatment is improved by more than several times and has very important use value. Because the benefits of cryogenic treatment can produce less resistance, reduce friction coefficient, less creep, improved flatness and easier machining.
Currently in aerospace and defense: optical housings, guidance systems, landing systems; automotive manufacturing: transmissions, brake parts, camshafts, bearings, ring gears, springs, etc .; cutting tools: tools, blades, drills, etc. are all in use Cryogenic treatment. The low temperature treatment of cutting tools can be divided into deep low temperature treatment (about -196 ° C) or shallow low temperature treatment (about -80 ° C).
Low temperature machining is useful in roughing operations to extend tool life. Maintain the integrity and quality of the processed surface during the finishing process
What kind of effect does the cryogenic cold box have on the tool:
1) It transforms lower hardness austenite into harder, stable, high abrasion resistance and heat resistance martensite;
2) Through ultra-low temperature treatment, the lattice of the material to be treated has widely distributed carbide particles with higher hardness and finer particle size;
3) It can produce even, tiny, and micro-structure with a large density in the metal grains;
4) In the cemented carbide to be treated, due to the reduction of its electronic kinetic energy, the molecular structure has a new combination.
5) The internal thermal stress and mechanical stress of the material after ultra-low temperature treatment are greatly reduced, thereby effectively reducing the possibility of cracks and chipping caused by tools and cutters. In addition, because the residual stress in the tool affects the cutting edge’s ability to absorb kinetic energy, the ultra-low temperature treated tool not only has higher abrasion resistance, but also its own residual stress is greatly reduced than the untreated tool;
6) Due to the additional micro-carbide particles and fine crystal lattice, it leads to a dense molecular structure, so that the tiny voids in the material are greatly reduced;
As more and more customers’ products need to be cryogenically treated, cryogenic cryogenic chamber equipment, as a necessary equipment, gradually entered the heat treatment manufacturers.