1) The tempering furnace equipment used in CNC machining is equipped with a cryogenic processing box that is continuously monitored by a computer and can automatically adjust the amount of liquid nitrogen entering and automatically raise and lower the temperature.
2) Treatment process The treatment process is composed of three programs: cooling, ultra-low temperature insulation and heating, which are accurately compiled.
The reason why cryogenic treatment of tempering furnace can improve performance is as follows:
1) It transforms lower hardness austenite into harder, more stable, higher abrasion resistance and heat resistance martensite;
2) Through ultra-low temperature treatment, the lattice of the material to be treated has wider distribution of carbide particles with higher hardness and finer particle size;
3) In the metal grains, a more uniform and finer microstructure with a greater density can be produced;
4) Due to the additional micro-carbide particles and finer crystal lattice, it leads to a denser molecular structure, and the tiny voids in the material are greatly reduced;
5) The internal thermal stress and mechanical stress of the material are greatly reduced after ultra-low temperature treatment, thus effectively reducing the possibility of cracks and chipping caused by tools and cutters. In addition, because the residual stress in the tempering furnace tool affects the cutting edge’s ability to absorb kinetic energy, the ultra-low temperature treated tool not only has higher wear resistance, but also its own residual stress is greatly reduced than the untreated tool;
6) In the cemented carbide to be treated, a new combination of molecular structures is generated due to the reduction of its electronic kinetic energy.