Research On Contact Characteristics Of Ball Bearing With Composite Rolling Body

As a key component of mechanical motion system,ball bearings are widely used in mechanical equipment because of high transmission efficiency and low friction coefficient.With the trend of high speed,heavy load and long life in the modern machinery industry,traditional ball bearings have some problems such as the big noise of vibration and premature fatigue and wear,which has seriously affected the normal operation of the equipment and production safety.Therefore,it’s necessary to develop a new type of ball bearings which are suitable under the condition of high-speed and heavy load and have the longer service life.Based on studying the contact performance of traditional ball bearings and analyzing the structure defect of ball bearings,the concept of composite ball bearings was proposed.Moreover,the contact performance of composite ball bearings was further studied through methods of theoretical analysis,finite element simulation and friction test.Main research contents of this paper are as follows:(1)Based on characteristics of two element composite structure of composite ball,advantages of composite ball bearings in the term of mechanical properties and extreme speed were analyzed.Then main factors affecting the performance and life of traditional ball bearings were analyzed synthetically.Combined with the internal load distribution of the composite ball bearing,the maximum shear stress and contact stress were proposed as analysis factors to optimize the performance and life of composite ball bearings.(2)Through Hertz theory and numerical analysis,the contact performance of ball bearings was analyzed and the numerical analysis method of composite ball bearings was obtained.Furthermore,the finite element simulation model of composite ball bearings was established.Under the heavy load working condition,the influence of elastic modulus and diameters of inner metal material on the contact performance of composite ball bearings were analyzed with Workbench.By comparing the contact performance of composite ball bearings with that of traditional ball bearings,the concept of composite ball bearings wasproved and validated.(3)Based on the simulation model of composite ball bearings,the suitable sample structure and processing technology were designed.The friction and wear testing machine suitable for the sample was further designed.The design procedure and selection of the core parts were introduced in detail and the intensity of the important parts was calculated and checked.By comparing and analyzing several sets to tests with single material,it was proved that the friction and wear test machine designed in this paper was stable and reliable.(4)Based on this test platform,friction tests were carried out with the optimized steel-titanium and steel-aluminum composite ball specimens.The variation trend of wear mark width and wear level were analyzed.Results have showed that the contact performance of the composite ball bearing proposed in this paper was better than that of the traditional ball bearing.And the performance of the composite ball bearing with the reasonable structure was more excellent.The composite ball bearing proposed in this paper was suitable for working conditions of high speed and heavy load,which provided a research direction for solving bearing vibration and premature fatigue failure.It’s of great significance to improve the stability and life of mechanical equipment.