Investigation of Surface Integrity Induced by Various Finishing Processes of AISI 52100 Bearing Rings

Materials

Guillaume Thoquenne¹  Philippe Revel²  Nabil Jouini³ 

[1] Centre Technique des Industries Mécaniques (CETIM), 52 Avenue Félix Louat, 60300 Senlis, France;Laboratoire Roberval de Mécanique FRE UTC-CNRS 2012, Université de Technologie de Compiègne, 60203 Compiegne, France;Mechanical Engineering Department, College of Engineering, Prince Sattam Bin Abdulaziz University, Alkharj 16273, Saudi Arabia;

关键词: finishing processes;    surface integrity;    bearing steel;    residual stresses;    rolling contact fatigue;   

DOI  :  10.3390/ma15103710

来源: DOAJ

【 摘 要 】

Surface integrity induced by finishing processes significantly affects the functional performance of machined components. In this work, three kinds of finishing processes, i.e., precision hard turning, conventional grinding, and sequential grinding and honing, were used for the finish machining of AISI 52100 bearing steel rings. The surface integrity induced by these finishing processes was studied via SEM investigations and residual stress measurements. To investigate rolling contact fatigue performance, contact fatigue tests were performed on a twin-disc testing machine. As the main results, the SEM observations show that precision hard turning and grinding introduce microstructural alterations. Indeed, in precision hard turning, a fine white layer (<1 μm) is observed on the top surface, followed by a thermally affected zone in the subsurface, and in grinding only, a white layer with 5 μm thickness is observed. However, no microstructural changes are found after sequential grinding and honing processes. White layers induced by precision hard turning and grinding possess compressive residual stresses. Grinding and sequential grinding and honing processes generate similar residual stress distributions, which are maximum and compressive at the machined surface and tensile at the subsurface depth of 15 μm. Precision hard turning generates a “hook”-shaped residual stress profile with maximum compressive value at the subsurface depth and thus contributes as a prenominal factor to the obtainment of the longest fatigue life with respect to other finishing processes. Due to the high quality of surface roughness (Ra = 0.05 μm), honing post grinding improves the fatigue life of bearing rings by 2.6 times in comparison with grinding. Subsurface compressive residual stresses, as well as low surface roughness, are key parameters for extending bearing fatigue life.

【 授权许可】

Unknown