The current status of furnaces for domestic heat treatment equipment are: more periodic furnaces, fewer continuous furnaces, low efficiency, and high energy consumption; more air furnaces, less atmosphere jealousy, serious oxidation and decarburization of workpieces, difficult quality assurance, low degree of automation, and human factors The influence is large, the quality is unstable, the proportion of the salt bath furnace is quite large, the labor conditions are poor, and the pollution is serious; more than half of the furnaces are more than 30 years old, and they are in disrepair, the thermal efficiency is low, the heat dissipation is serious, and the cost is high. Since the reform and opening up, China has introduced a large number of heat treatment equipment from the United States, Japan, Germany, Switzerland, Austria and other countries, including sealed box multi-purpose furnaces, air heat treatment furnaces, and induction heating equipment. Nevertheless, there is still a considerable gap between the requirements of relatively advanced industrial countries and the booming industrial construction, and the overall level is very low.
At present, the application of computers is the only way to transform and modernize traditional heat treatment technologies. It includes three aspects: one is the application of computer in heat treatment parameters and management, the other is the application of computer control in the production process, and the third is the application of computer in equipment manufacturing process. China ’s self-developed technology for controlling the distribution of the concentration of permeated layers has been used in production. Microcomputer-based dynamic control of nitriding and dynamic carbon potential control technology have been included in the “National Key Scientific and Technological Achievements Promotion Plan” in 1993, and the promotion is good. The industrial electric furnace CAD system suitable for electric furnace plants has been running for many years. The system has 24 terminals. In addition to computer drawing, basic library and graphic file management functions, it is also equipped with a comprehensive database and basic calculation subsystem for electric furnace design. The heat treatment equipment system can free the designer from tedious and repetitive labor and engage in creative work.
Vacuum heat treatment equipment has the advantages of no oxidation, no decarburization, bright workpiece surface, small deformation, no pollution, energy saving, high degree of automation, and a wide range of applications. It is one of the new heat treatment technologies that have developed rapidly in recent years, especially Great progress has been made in the surface modification of aviation materials. Many newly developed advanced heat treatment technologies, such as vacuum high pressure gas quenching and vacuum chemical heat treatment, also need to be implemented under vacuum. The use of vacuum heat treatment technology can greatly improve the quality and service life of structural materials, tools and molds, and is especially suitable for the heat treatment of some precision parts. With the development of vacuum heat treatment technology, vacuum heat treatment equipment such as vacuum tempering furnace, vacuum quenching furnace, vacuum annealing furnace, vacuum carburizing furnace, vacuum sintering furnace, and vacuum brazing furnace have been successfully developed in China. The level of manufacturing technology and equipment has been continuously improved, and the degree of vacuum has gradually reached the international level. However, there is still a certain gap with foreign countries in the automation control and fine processing of devices, especially for the stability of ultra-high vacuum furnaces. Improved preparation level.
In developed countries, the proportion of vacuum heat treatment equipment has reached about 20%, while China currently has about 1,200 vacuum heat treatment furnaces, accounting for about 1% of the total number of heat treatment furnaces, and the gap with foreign countries is very large. It is expected that with the heat treatment industry in the future The technological progress and the higher requirements for the quality of heat-treated workpieces, vacuum heat treatment will have a greater development. Ion nitriding, as a surface chemical heat treatment process, has a series of advantages: fast nitriding speed, easy control of the structure of the nitriding layer, small distortion, good mechanical and physical properties such as hardness, brittleness, and abrasion resistance; surface before and after nitriding Simple cleaning process; easy to achieve local nitriding; saving energy and raw material consumption and reducing environmental pollution. Therefore, once this technology came out, it was valued, it developed rapidly in the 1970s, and it became more and more widely used in production. With the development of electronic technology and computer technology, the emergence of high-power electronic and electrical components, the power and control technology of ion nitriding equipment has been greatly improved.