Heat treatment quality is directly related to the quality of subsequent processing, and finally affects the function and life of parts.At the same time, heat treatment of plain bearings is the main power consumption and pollution in the mechanical industry.
Over the years, with the development of science and technology and its application in heat treatment, the development of heat treatment technology is as follows:
(1) cleaning heat treatment
Waste water, waste gas, waste salt, dust, noiseless bearings and electromagnetic radiation from heat treatment all pollute the environment.In order to solve the environmental pollution caused by heat treatment, clean heat treatment (or green heat treatment) is one of the development directions of heat treatment technology in developed countries.In order to reduce SO_2, CO, CO_2, dust and cinder emissions, basically coal has been used as fuel, heavy oil is used less and less, light oil is used more and more, and natural gas is still the best fuel.The use of waste heat from incinerators has reached a high level.Optimize the self - lubricating bearing structure, strictly control the air - fuel ratio, under the premise of reasonable incineration, reduce NOX and CO to a minimum.Gas carburizing, carbonitrogenation and vacuum heat treatment were used instead of salt bath treatment to reduce the pollution of waste salt and toxic substances containing CN to water source.Some quenchants were replaced by water-soluble quenchants, and some mineral oils were replaced by biodegradable vegetable oils to reduce oil pollution.
Fine heat treatment
Fine heat treatment has two meanings: one is according to the parts of the application requirements, data, construction scale, the use of physical metallurgy knowledge, grasp the computer simulation detection technology, optimize the process parameters.To achieve the desired functionality or to maximize the potential of the data;On the other hand, it is sufficient to ensure the stability of the optimization technique, the mass dispersion of the finished product is very small (or zero), and the heat treatment deformation is zero.
Energy-saving heat treatment
Scientific production and power management are the most potential elements for the effective use of power.It is the choice of scientific management to establish professional heat treatment equipment to ensure the full production and full performance of the equipment.In the structure of heat treatment power supply, the primary power supply should be preferred.Make full use of residual heat and residual heat;Choose the technology with low energy consumption and short cycle to replace the technology with long cycle and high energy consumption.
Less oxidation - no heat treatment
From choosing to maintain atmosphere heating instead of oxidizing atmosphere heating to precisely controlling carbon potential and nitrogen potential to control atmosphere heating, the function of parts after heat treatment is improved, and heat treatment defects such as decarburization and cracking are greatly reduced.After heat treatment, the retention rate of final processing is reduced, and the computing rate and processing capacity of data are improved.Vacuum heating, gas quenching, vacuum or low pressure carburizing, nitriding, nitriding, boronizing, etc., can significantly improve the quality, reduce deformation, improve life.
The heat treatment quality control of bearing parts is the strictest in all mechanical industries.The heat treatment of bearing has made great progress in the past 20 years.The following are the most important aspects: the basic theory of heat treatment;Research on heat treatment technology and application skills;Development of new heat treatment equipment and related technologies.