Carburizing technique for medium carbon steel cold rolled bearing case loop

Abstract

The invention discloses a carburizing process for cold rolling the bearing ring through medium carbon steel, which belongs to the technology field of heat treatment. A circular ring is made of tubes or bar stock through punching or forging into wafer after annealing, and made into a bearing ring through cold rolling; then carburizing heat treatment process is performed; in the carburizing atmosphere of 1.15 percent of carbon potential, direct quenching is performed after carburizing is performed for 10 hours at the temperature of 850 to 870 DEG C; the tempering temperature is 150 to 160 DEG C, and the temper time is 3 to 4 hours. The medium carbon steel bearing ring after being treated through the carburizing process has higher toughness and longer fatigue life; particularly, for the bearing working under the contaminated environment, the service life and the operational reliability can be improved.

Description

technical field [0001] The invention belongs to the technical field of heat treatment, and in particular relates to a carburizing process for cold rolling bearing rings of medium carbon steel. Background technique [0002] Most of the commonly used materials for bearing rings are high-carbon chromium bearing steel, which has a high carbon content. Even after annealing, the cold deformation resistance is still high, which affects the cold rolling performance and the service life of the mold. The rolling ring is prone to cracks and becomes a waste product. Famous foreign bearing companies such as NSK, etc., developed medium-carbon alloy steel bearing rings in the 1990s, and adopted a special heat treatment process, which can greatly improve the bearing life, especially under the condition of polluted lubrication. . [0003] Medium carbon steel has good cold rolling performance. Through cold rolling, it can save material and improve structure. The special heat treatment proce...

AI Technical Summary

Problems solved by technology

[0003] Medium carbon steel has good cold rolling performance. Through cold rolling, it can save material and improve structure. The special heat treatment process can greatly improve the bearing life, especially the bearing life under the condition of polluted lubrication, but for medium carbon steel The carburizing heat treatment process of the bearing ring has not been reported yet