Research On Quantitative Of Outer Ring Crack Fault Size And Location Of Full Ceramic Ball Bearing

With the development of manufacturing industry in recent years,mechanical equipment on the rolling bearing performance continues to improve,full ceramic ball bearings in aerospace,high-end machine tools and metallurgical equipment and other fields gradually replace the traditional steel bearings gradually occupy a dominant position.When full ceramic bearing is running,the outer ring damage is one of the main reasons for the failure of full ceramic bearing,which affects the working performance of the bearing.Due to the high hardness and brittleness of industrial ceramic materials,the operating performance of full ceramic ball bearing is very sensitive to the size and location of the outer ring failure.The main failure forms of the outer ring of full ceramic ball bearing are spalling and crack.The two kinds of failure often occur in the outer ring of full ceramic ball bearing at the same time.Considering the common failure forms of full ceramic ball bearing,the influence of outer ring crack on the working performance of full ceramic ball bearing is more serious than that of spalling.Therefore,this paper mainly focuses on the analysis of the crack size and location on the outer ring of full ceramic ball bearing.The main work is as followsFirstly,the quantitative research on the cracks derived from the spalling fault of the outer ring of full ceramic ball bearing is carried out.When the spalling fault occurs on the outer ring of full ceramic ball bearing,the crack morphology is divided into open mode crack and mixed mode crack according to the different crack generation mechanism at the spalling fault location of the outer ring.The force exerted on the outer ring during the rolling element passing through the spalling fault location of the outer ring is analyzed by calculating the failure impact force function model of full ceramic ball bearing outer ring spalling failure,the dynamic model of full ceramic ball bearing outer ring spalling failure is established.Considering the mechanism of open mode crack,the functional relationship between the outer ring crack size and the strain energy release rate at the crack is established through the fracture mechanics of ceramic materials based on the change of strain energy of ceramic outer ring,the time-varying stiffness of open mode crack in outer ring with spalling fault is deduced,and the failure dynamic model of open mode crack at spalling position of outer ring is established to quantitatively study the outer ring fault.Secondly,for the quantitative study of the mixed mode crack size derived from the spalling failure of the outer ring of full ceramic ball bearing,the load distribution of the spalling failure of the outer ring of full ceramic ball bearing is analyzed by the quasi-static method.Considering the mechanism of the mixed mode crack at the spalling position of the outer ring,the load distribution of the crack position is analyzed by the method of micro fracture mechanics of ceramic materials combined with spalling The functional relationship between the scale of mixed mode crack and the strain energy release rate is established,and the time-varying stiffness of mixed mode crack in the outer ring with spalling fault is deduced by combining with the change of strain energy of the ceramic outer ring.The fault dynamics model of mixed mode crack derived from spalling position of the outer ring is used to quantitatively study the outer ring fault.By comparing the experimental results with the study of open mode crack and mixed mode crack in the spalling position,the proportion of two kinds of cracks in the spalling process of full ceramic ball bearing outer ring and the influence of crack size on the fault signal characteristics are analyzed.Thirdly,aiming at the quantitative research of the outer ring position of full ceramic ball bearing,the outer ring fault dynamic model of full ceramic ball bearing is established.Considering the vibration attenuation of fault vibration signal along the outer ring,the vibration attenuation matrix is constructed,and the outer ring position recognition model of full ceramic ball bearing is established.The simulation results are analyzed,and the root mean square difference of fault vibration signal and the outer ring fault location are deduced according to the function relation of the position of the outer ring,and the outer ring position of full ceramic ball bearing is studied quantitatively.The simulation results show that the method is feasible.The size and location of the derived cracks at the spalling position of the outer ring of full ceramic ball bearings are quantitatively studied by the method of dynamic model.Establishing the relationship between the outer ring cracks of different size and positions and the motion response characteristics of full ceramic ball bearings provides a theoretical basis for fault diagnosis and health monitoring of full ceramic ball bearings,and in order to ensure the safety of full ceramic ball bearing in the working process,it has great practical significance.