Manufacturing method capable of improving strength and toughness of cold-ring-rolled bearing ring and improving quenching deformation

Abstract

The invention discloses a manufacturing method capable of improving the strength and toughness of a cold-ring-rolled bearing ring and improving quenching deformation. The manufacturing method comprises the following steps: S1. cold-ring-rolling forming: carrying out rolling forming on a ring blank of the bearing ring through a cold-ring-rolling process; and S2. firstly, slowly heating the rolled-formed bearing ring to reach a certain temperature and carrying out recrystallization, and insulating heat for a period of time to eliminate the residual stress of cold-rolling; secondly, rapidly heating the bearing ring to reach a certain temperature and carrying out austenization; thirdly, carrying out pre-quenching treatment on the bearing ring and insulating heat, and forming lath martensites in partial low-carbon areas; fourthly, heating the bearing ring to reach a certain temperature and insulating heat, and carrying out bainite transformation; and finally, cooling the bearing ring to reach room temperature. According to the manufacturing method disclosed by the invention, the change of a ferrite matrix and spheroidized carbides is caused by virtue of cold-rolling plasticity, the pre-quenching process and the bainite phase-change heat treatment process are matched, and the microstructure of a material is controlled, so that the qualification rate of finished bearing rings is greatly increased, the strength and toughness of the material are greatly improved, and the fatigue life of the material is greatly prolonged.

Description

technical field [0001] The invention belongs to the technical field of mechanical manufacturing, and in particular relates to a manufacturing method for improving the strength and toughness of cold ring rolling bearing rings and improving quenching deformation. Background technique [0002] As a key component of major equipment such as high-speed railways, precision machine tools, and wind turbines, the technical level of bearings directly determines the overall development level of the entire equipment manufacturing industry. Bearings include rings (including inner rings and outer rings), rolling elements and cages. Among them, the weight and manufacturing cost of rings account for 60-70% of the entire bearing product, and they are the most important components of bearings. Bearings The service life depends on the microstructure state of the bearing ring. [0003] For bearing rings made of GCr15 bearing steel as the main material, the traditional manufacturing process incl...

AI Technical Summary

Problems solved by technology

Turning is used to form the ferrule, the cutting allowance is large, and the material utilization rate is low; on the other hand, after the traditional martensite quenching and tempering heat treatment, a composite material composed of tempered martensite, retained austenite and carbide is obtained. Although this kind of microstructure mainly composed of tempered martensite can meet the performance requirements of ordinary bearings, for precision bearings that need to operate under more complex and high-speed service conditions, the traditional heat treatment process can no longer meet the requirements. its service requirements

In addition, the bearing ring introduces a large amount of internal stress during the forming and heat treatment process. The traditional heat treatment method cannot effectively eliminate the residual stress, resulting in problems such as out-of-tolerance deformation of the bearing ring, high scrap rate, and increased manufacturing costs.

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