Experimental Investigation On Anti-wear Properties And Numerical Simulation Of Automobile Gears With Bionic Concave Morphology

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.