滑动轴承表面椭圆偏置类抛物线微织构研究

Elliptic Bias Parabolic Micro-texture of Sliding Bearing Surface

目的 充分发掘微织构对于提高滑动轴承的承载性能和抗摩擦磨损性能的潜力。方法 选取某系列汽车发动机活塞连杆组件中的滑动轴承为原型,采用CFD方法对该轴承的承载性能和摩擦性能进行分析。综合运用正交试验和灰色关联分析理论,通过有限元仿真分析方法研究椭圆开口偏置类抛物线微织构结构参数对织构轴承承载力和摩擦因数的影响规律,对其进行多目标优化设计。在此基础上,基于响应面优化设计理论,运用有限元仿真分析方法研究微织构分布参数对织构轴承承载力和摩擦因数的影响规律,建立相应的数学模型并对其进行多目标优化设计。将具有最优参数微织构的滑动轴承的承载性能和摩擦因数与原型轴承进行对比。结果 微织构的最优参数为椭圆长、短半轴长分别为200μm和110μm,深度和对称轴的偏移量分别为60μm和30μm,起始角和包角分别为4.65°和116.75°,间距为2.79 mm。在滑动轴承表面加工椭圆偏置类抛物线微织构后,其承载力相较于原型滑动轴承增加了21.05%,摩擦因数降低了27.93%。结论 在滑动轴承表面加工出具有最优参数的椭圆偏置类抛物线微织构可以极大地提高滑动轴承的承载性能和摩擦性能。

Surface texture technology is to process nano micro texture with specific shape and size and special arrangement on the moving friction surface according to people’s will by mechanical processing, chemical or physical methods. In this paper,the effect of elliptic opening bias parabolic microtexture on bearing capacity and friction and wear resistance of plain bearing and its multi-objective parameter optimization are studied.A four-factor and five-level orthogonal experimental table was established, and Workbench software was used to analyze the bearing capacity and friction coefficient of sliding bearings under different micro-texture structural parameters. The range analysis method was used to analyze the influence of microtexture structural parameters on the bearing capacity of sliding bearing oil film in the order of microtexture depth > long half-shaft length > offset > short half-shaft. The order of influence on friction coefficient is as follows: long semi-axial length > micro-texture depth > offset > short semi-axial length. The optimal microtexture parameters are 200 μm long half axis of the ellipse, 110 μm short half axis of the ellipse, 60 μm depth and 30 μm offset. The establishment and the optimal structure parameters of the micro texture open area ratio, the depth the same, no circular openings of the deviation of the symmetric parabolic micro texture, by comparing the oil film bearing capacity and the friction coefficient of the two, prove that compared with the circular opening micro texture elliptic offset class parabolic micro texture on the bearing performance and friction performance of the sliding bearing to improve better.The influence of micro-texture distribution parameters on the bearing performance and friction coefficient of sliding bearings was analyzed by response surface analysis(RSM). The influence degree of distribution parameters on bearing capacity of sliding bearing oil film is as follows: micro-texture envelope angle > micro-texture axial spacing > micro-texture starting angle. The influence degree of friction coefficient on sliding axis is as follows: micro-texture initial angle > micro-texture axial spacing > micro-texture envelope angle. At the same time, a mathematical model was established for the bearing performance and friction coefficient of sliding bearing with the variation of micro-texture distribution parameters. Then, with the optimal bearing performance and the minimum friction coefficient as the objective function, the distribution parameters of micro-texture were optimized. After optimization processing, The optimal microtexture distribution parameters were obtained as follows:microtexture inclusion angle 4.65°, microtexture starting angle 116.75° and microtexture axial spacing 2.79 mm.The optimal parameters of ellipse openings will offset parabolic sliding bearing of the bearing capacity and the friction coefficient is simulated, and its results and the prototype of smooth sliding bearing and the established model prediction were compared, the results show that the established on the basis of micro texture distribution parameters on the micro texture predict the bearing capacity and the friction coefficient of sliding bearing of the mathematical model with sufficient accuracy;Compared with the prototype sliding bearing, the bearing capacity of the optimal micro-texture sliding bearing increases by 21.05%, while the friction coefficient decreases by 27.93%. In a word, the bearing performance and friction and wear resistance of plain bearings can be greatly improved by machining elliptical bias parabolic microtexture with optimal structure and distribution parameters.