硬渗氮保持架断裂分析

Fracture Analysis of Nitriding Cage

某型号深沟球轴承的保持架在上机安装时发生碎裂,于是采用化学成分分析、金相组织检验、维氏硬度检验及扫描电镜等技术,对该轴承保持架碎裂原因进行了分析。结果表明:该深沟球轴承保持架表面硬渗氮层厚度不均匀且不连续,该保持架硬度与未断裂保持架相比略高。安装时失效保持架受力造成应力叠加,在渗氮层不连续处最易发生裂纹,从而引起保持架碎裂。

The fracture reason of the cage of deep groove ball bearing during installation on the machine was analyzed by means of chemical composition analysis, metallographic examination, Vickers hardness examination and scanning electron microscope. The results show that the thickness of hard nitriding layer on the surface of the cage is uneven and discontinuous, and the hardness of the cage is slightly higher than that of the unbroken cage. When the failure cage is installed, the stress is superposed, and the crack is easy to occur at the discontinuity of nitriding layer, which causes the cage to break.