轴承套圈碳氮共渗工艺的改进

Improvement of carbonitriding process for bearing rings

针对常规碳氮共渗处理后高碳铬轴承表面组织粗大和废品率高的问题,对现有工艺进行改进。在原有碳氮共渗+淬火回火工艺基础上,在碳氮共渗后增加了空冷环节。结果表明,改进后工艺有效解决了渗层深度和组织级别的矛盾,改善了马氏体组织级别。对比常规碳氮共渗工艺,经改进后工艺处理得到的轴承内圈尺寸畸变量小,表面组织和硬度能够满足要求,疲劳寿命达到5.5L10。

To address the issues of coarse surface structure and high scrap rate of high carbon chromium bearings after conventional carbonitriding treatment,improvements were made to the existing process.On the basis of the original carbonitriding+quenching and tempering process,an air cooling process was added after carbonitriding.The results show that the improved process effectively resolves the contradiction between the depth of infiltration layer and the level of microstructure,and improves the level of the martensite.Compared with the conventional carbonitriding process,the improved process results in smaller size distortion of the bearing inner ring,satisfactory surface microstructure and hardness,and the fatigue life of 5.5L10.