Development Trend of Heat Treatment Technology of Hardware Bearings

Bearing heat treatment is directly related to the subsequent processing quality, which ultimately affects the performance and life of parts. At the same time, bearing heat treatment is a major energy consumer and a major polluter in bearing manufacturing. The bearing heat treatment equipment directly affects the bearing heat treatment quality, as well as energy consumption and pollution. In recent years, with the advancement of science and technology, the development trend of heat treatment technology is mainly reflected in the following aspects:

　(1) Waste water, waste gas, waste salt, waste generated from the production of clean heat treatment Oil and electromagnetic radiation will pollute the environment. To solve the environmental pollution problem of heat treatment, the implementation of clean heat treatment (or green heat treatment) is one of the development directions of heat treatment technology. This puts high demands on the heat treatment atmosphere, quenching oil and cleaning equipment.

　　(2) Precision heat treatment Precision heat treatment is to fully ensure the stability of the optimized process, realize the product quality dispersion is very small (or zero), the heat treatment distortion is zero, reduce the grinding allowance and improve the production efficiency. Save materials. The realization of precision heat treatment must have good furnace temperature uniformity, temperature control accuracy, and good cooling and stability of the quenching agent. To realize the precision heat treatment of the bearing, two ways can be taken: integral quenching and induction quenching.

　　 (3) Energy-saving heat treatment selects new thermal insulation materials to improve the energy efficiency of heat treatment equipment; optimize the heat treatment process, increase the process output, and give full play to the capabilities of the equipment. At this stage, various bearing manufacturers are doing experiments in this area, such as making full use of waste heat and waste heat. Some manufacturers have used forging waste heat to spheroidize and anneal bearing parts; use low-energy and short-cycle processes to replace long and high-energy-consuming processes. To a certain extent and within a certain range, the lower bainite quenching process has replaced the long-period and energy-consuming carburizing process with a shorter bainite quenching process.

　　(4) Less non-oxidizing heat treatment is replaced by protective atmosphere heating instead of oxidizing atmosphere heating to a controlled atmosphere heating that precisely controls the carbon potential and nitrogen potential. After the heat treatment, the performance of the parts is improved, and the heat treatment defects such as oxidation, Decarburization and cracks are greatly reduced, and the amount of finishing remaining after heat treatment is reduced, which improves the utilization rate of materials and machining efficiency. Vacuum heating gas quenching, vacuum or low-pressure carburizing, nitriding, nitrocarburizing and boronizing can significantly improve the quality of the workpiece, reduce distortion, and increase life.