Atomic-Scale Insights into Damage Mechanisms of GGr15 Bearing Steel Under Cyclic Shear Fatigue  

作　　者：Qiao-Sheng Xia Dong-Peng Hua Qing Zhou Ye-Ran Shi Xiang-Tao Deng Kai-Ju Lu Hai-Feng Wang Xiu-Bing Liang Zhao-Dong Wang 

机构地区：[1]State Key Laboratory of Solidification Processing,Center of Advanced Lubrication and Seal Materials,Northwestern Polytechnical University,Xi’an,710072,China [2]State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang,110819,China [3]Defense Innovation Institute,Academy of Military Science,Beijing,100071,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2024年第7期1265-1278,共14页金属学报（英文版）

基　　金：the Natural Science Foundation of China(No.52175188);the Key Research and Development Program of Shaanxi Province(No.2023-YBGY-434);the Open Fund of Liaoning Provincial Key Laboratory of Aero-engine Materials Tribology(No.LKLAMTF202101);the State Key Laboratory for Mechanical Behavior of Materials(No.20222412);the Fundamental Research Funds for the Central Universities.

摘　　要：Alternating shear stress is a critical factor in the accumulation of damage during rolling contact fatigue,severely limiting the service life of bearings.However,the specific mechanisms responsible for the cyclic shear fatigue damage in bearing steel have not been fully understood.Here the mechanical response and microstructural evolution of a model GGr15 bearing steel under cyclic shear loading are investigated through the implementation of molecular dynamics simulations.The samples undergo 30 cycles under three different loading conditions with strains of 6.2%,9.2%,and 12.2%,respectively.The findings indicate that severe cyclic shear deformation results in early cyclic softening and significant accumulation of plastic damage in the bearing steel.Besides,samples subjected to higher strain-controlled loading exhibit higher plastic strain energy and shorter fatigue life.Additionally,strain localization is identified as the predominant damage mechanism in cyclic shear fatigue of the bearing steel,which accumulates and ultimately results in fatigue failure.Furthermore,simulation results also revealed the microstructural reasons for the strain localization(e.g.,BCC phase transformation into FCC and HCP phase),which well explained the formation of white etching areas.This study provides fresh atomic-scale insights into the mechanisms of cyclic shear fatigue damage in bearing steels.

关 键 词：Cyclic shear fatigue Molecular dynamic simulation Bearing steels Plastic damage accumulation 

分 类 号：TG142.71[一般工业技术—材料科学与工程]