Zhou Guanghua, Wei Wenting, Liu Qinglong
School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China.
Hubei Key Laboratory of Advanced Technology for Automotive Components, Wuhan University of Technology, Wuhan 430070, China.
Materials (Basel). 2020 Sep 30;13(19):4355. doi: 10.3390/ma13194355.
The hot ring rolling technology as the crucial procedure for the manufacture of bearing rings plays an important role in determining the final microstructure of bearing rings. In this work, the influence of the hot ring rolling process on the microstructural evolution of 100Cr6 bearing rings was investigated using a three-dimensional (3D) numerical model and microstructural characterization. It was found that the significant microstructural refinement occurs at the different regions of the rings. However, owing to the non-uniform plastic deformation of hot rolling, the refinement rate of grain size and decrease of pearlite lamellar spacing (PLS) also showed uniformity at different regions of the rings. Furthermore, the degree of grain refinement had been limited with the increase of rolling reduction. Due to the refined grain size and decreased PLS, the Vickers hardness increased with the increase of rolling reduction. Moreover, the Vickers hardness from the outer surface to the inner surface of the ring is asymmetrical u-shaped, which had the law of lower hardness in the center area and higher hardness on the surface.
热环轧工艺作为轴承套圈制造的关键工序，在决定轴承套圈最终微观组织方面起着重要作用。在这项工作中，利用三维（3D）数值模型和微观组织表征，研究了热环轧工艺对100Cr6轴承套圈微观组织演变的影响。研究发现，在套圈的不同区域发生了显著的微观组织细化。然而，由于热轧塑性变形不均匀，晶粒尺寸的细化速率和珠光体片层间距（PLS）的减小在套圈的不同区域也表现出不均匀性。此外，随着压下率的增加，晶粒细化程度受到限制。由于晶粒细化和PLS减小，维氏硬度随压下率的增加而增加。而且，套圈从外表面到内表面的维氏硬度呈不对称的u形，中心区域硬度较低，表面硬度较高。
