Mold heat treatment technology and trend analysis of the status quo
Mold performance of heat treatment is an important tool to ensure that the process for the manufacture of precision molds, mold strength, the working life of mold, mold manufacturing costs have a direct impact. 20th century since the 80's, the international mold heat treatment of the field of rapid technological development is the vacuum heat treatment technology, mold and mold surface hardening technology of pre-hardened materials technology. Vacuum heat treatment technology dies
Vacuum heat treatment technology is developed in recent years a new type of heat treatment technology, it has the characteristics of the mold is urgently needed, such as to prevent oxidation and decarburization heating, vacuum degassing or in addition to gas, the elimination of hydrogen embrittlement, thereby enhancing the material (parts) of plasticity, toughness and fatigue strength. Vacuum heating slow, small parts inside and outside factors such as temperature, determines the result of vacuum heat treatment process, such as parts of small deformation.
Die vacuum heat treatment is the main application of vacuum cooling quenching oil, vacuum gas-cooled quenching and tempering vacuum. In order to maintain the workpiece (such as mold) of the excellent characteristics of vacuum heating, cooling agents and the choice of cooling technology and the development of very important, tool mainly by oil quenching and air cooling. The heat treatment carried out after the machining is no longer face of the mold, after quenching, as far as possible the use of vacuum annealing, vacuum hardening, especially the workpiece (mold), which can improve the surface quality and mechanical properties, such as fatigue performance, the surface brightness, corrosion resistance and so on.
Heat treatment process, the success of computer simulation technology development and application of intelligent mold heat treatment makes it possible. Because of the low-volume production molds (or even one-piece), the characteristics of multi-species, as well as the high performance requirements of the heat treatment and the characteristics of waste are not allowed there, but also allows heat treatment as a tool to be intelligent. Foreign industrial countries, such as the United States, Japan and so on, in a vacuum high pressure gas quenching, the development soon, the main target is the mold.
Mold surface treatment technology
Mold in the workplace in addition to the requirements of the matrix with a sufficiently high strength and toughness of reasonable co-ordination, the surface performance of the work of die essential performance and service life. Mold surface treatment technology, through the surface coating, surface modification or composite processing technology, changes in surface morphology, chemical composition, organizational structure and stress state in order to obtain the required surface properties of systems engineering. At present the application of mold is more nitriding, carburizing and hardening film deposition.
Nitriding technology as a result of the excellent performance of the formation of the surface, and nitriding process for hardening die steel with good co-ordination process, at the same time low nitriding temperature, nitriding without intense after cooling, the deformation of a very small die, so die Surface nitriding technology used earlier, but also the most widely used.
Die Die carburizing is to increase the overall strength and toughness, that is, the work mold surface with high strength and wear resistance. Hardening film deposition technology is currently more mature cvd, pvd. Mold from the 80's last century began to use film coating technology sclerosis. Current technical conditions, the hardening film deposition techniques (mainly equipment) costs are relatively high, is still only in a number of sophisticated, long-life application of mold, if the way the establishment of treatment centers, the hardened coating film will significantly reduce the cost of more die if this technology can improve the overall level of the mold manufacturing.
Pre-hardened mold material technology
