【作者】 董立春；

【导师】 韩志武；

【作者基本信息】 吉林大学 ， 仿生科学与工程， 2010， 博士

【摘要】 汽车齿轮是传递行驶动力的主要部件,其耐磨性能的好坏直接影响齿轮的使用寿命。由于汽车齿轮传动本身具有重复性强,连续工作的特点,加之又在循环交变应力的作用下,其齿面啮合区域经常磨损很严重,导致轮齿齿面疲劳失效,发生点蚀、胶合等现象,降低了齿轮的使用寿命,影响汽车的正常运行。因此,如何提高齿轮的耐磨性及延长其使用寿命成为目前汽车齿轮行业急需解决的难题。本论文是在已有的仿生耐磨设计与制造技术研究的基础之上,针对汽车齿轮磨损严重的问题,以模型试验为基础,设计制作了凹坑型仿生形态汽车齿轮,从功能表面仿生角度来解决这一问题。将齿轮的啮合传动简化成了两个圆柱体的表面既有相对微小滑动,又有啮合滚动的运动形式;在模型试验中,设计了九种不同尺寸与分布的微观凹坑型仿生表面形态,利用激光图形雕刻技术在环块样件的外表面加工形成了九种凹坑型仿生形态,进行了光滑与凹坑型仿生形态环块样件的摩擦磨损对比试验,试验表明仿生形态样件耐磨性可以提高41%。利用ANSYS有限元分析软件,完成了光滑与凹坑型仿生形态环块样件接触问题三维数值模拟,得到了光滑与凹坑型仿生形态环块样件接触的等效应力、接触应力与接触渗透量的分布云图,并对比了光滑与凹坑型仿生形态环块样件应力大小,九种凹坑型环块样件接触的等效应力、接触应力与接触渗透量均大于光滑样件。采用齿轮疲劳磨损试验机,进行了光滑与凹坑型仿生形态汽车齿轮耐磨性能对比试验研究;通过试验前后齿向与齿形误差值轨迹的对比,定性地分析了光滑与凹坑型仿生形态汽车齿轮磨损特性;通过试验前后齿向误差值与齿形误差量值的对比,定量地分析了光滑与凹坑型仿生形态汽车齿轮磨损量的规律,仿生形态齿轮可以提高耐磨性58%。利用ANSYS有限元分析软件,完成了光滑与凹坑型仿生形态齿轮二维与三维接触问题数值模拟,并进行了其接触的等效应力与接触应力的对比分析。等效应力与接触应力最大值均出现在大齿轮齿顶与小齿轮齿根接触位置,凹坑形态齿轮接触面区域的接触应力值明显小于光滑形态齿轮。根据齿轮弹性流体动力润滑理论的基本计算公式,运用MATLAB软件,完成了光滑与凹坑型仿生形态齿轮接触等温弹流润滑问题数值计算。更多还原

【Abstract】 The automobile gear is the main component of transferring power, the quality of anti-wear properties dominates service lives of gear directly. Because of the characteristics of the gear transmission, which usually occurred in the continuous working state, the working condition is very bad. The tooth face wears away seriously, and the gear tooth often runs down because of the mesh abrasion. It is more seriously to appear pitting corrosion, felting, which causes the gear not rotating normally, and the service lives of gear is depressed accordingly. Therefore, how to improve the anti-wear properties and service lives of gear is an currently urgent problem to be solved for gear industry. There are many methods to improve anti-wear properties in the tradition, such as, changing material, heat treatment method, spraying abrasion coatings material, etc..The wear away problem is still very serious, which is payed attention to the bionics scholar.It was found that in the bionics, some soil animals, for example, the dung beetle, gryllotalpa and etc., its non-smooth morphology of the body surface showed highly wear-resistant features, The wear mechanism has been confirmed by a large number of scientific experiments, and used effectively in many fields such as mechanics engineering, material science, aviation and navigation in and abroad. According to the problem of serious wearing of the gear, the bionics researchers used the optimizing analysis of the existing model, designed and produced the unsmooth gear to resist the wearing and tried to solve the problem from the configuration and function.Nine concave surface morphology have been designed in the experiment of model, and laser texturing technology was used to process the surface of the model in this paper. In the same conditions, comparative experiment has been already completed between smooth model and bionic concave model. According to the measuring result of weight before and afer experiment, the wear value and the wear rate, the wear value and the wear rate of ten different models have been analysed contrastively. the range analysis was adopted for the wear value and the wear rate of nine different models by the way of orthogonal experimental design. In the lubrication condition, the anti-wear properties of bionic concave models were better than that of the smooth model, and the anti-wear mechanism of bionic concave models was analysed.The software ANSYS was used to process three-dimensional finite element numerical simulation between smooth model and bionic concave model. Without lubrication condition, the finite element analysis of nine bionic concave models have been completed by ANSYS for contact problem, and the stress nephogram of von mises stress, the stress intensity, contact stress, the contact penetration were displayed respectively, the stress results of smooth model have been compared with the nine bionic concave of form von mises stress, stress intensity, contact stress, contact penetration.Wear testing machine of gear was used to carry out the comparative experiment between smooth gears and bionic convave gears of automobile.The surface morphology parameters of the gear were measured before and after experiment, and the curve of error and the error value were got. The comparative analysis has been completed about profile error and tooth trace error before and after abrasion experiment, and the qualitative and quantitative analysis have been completed about the quality of wear resistance.The graphics software of CAXA was used to create two-dimensional model of gears. The two-dimensional model was imported to ANSYS, and the finite element model of gears was created. In the same parameter settings, the software of ANSYS was adopted to simulate two-dimensional contact problem between smooth gears and bionic concave gears, and the stress nephogram of the von mises stress and the contact stress were displayed respectively, and the comparative analysis of the von mises stress and the contact stress have been completed. The maximum von mises stress and contact stress appeare at the contact position of the large and small gears, although the von mises stress of bionic concave gears was greater than that of the smooth gear, the contact stress of bionic concave gear was less than that of the smooth gear significantly.The graphics software of CATIA was used to create three-dimensional model of gears. The three-dimensional model was imported to ANSYS, and the finite element model of gears was created. In the same parameter settings, the software of ANSYS was adopted to simulate three-dimensional contact problem between smooth gears and bionic concave gears, the stress nephogram of the von mises stress and the contact stress were displayed respectively. The comparative analysis of the von mises stress and the contact stress have been completed. The maximum von mises stress and the contact stress appeare at the contact position of the large and small gears as well, although the von mises stress of bionic concave gears was greater than that of the smooth gear, the contact stress of bionic concave gear was less than that of the smooth gear significantly.According to the basic equation of Reynolds for elastic hydrodynamic lubrication of gear, in the lubrication conditions, the basic equations, which is elastic hydrodynamic lubrication of smooth gears and bionic concave gears, was deduced respectively, and the numerical calculation of elastic hydrodynamic lubrication of smooth gears and bionic concave gears have been completed, the relation between the thickness of the film and the pressure of film have been established.更多还原