The Study On Simulation Method Of Pin-on-disc Sliding Wear Test

Tribological simulation was a new study problem developed from modern information technology and computer simulation technology in combination with a variety of mathematical methods in the field of tribology. Due to the complexity of actual tribological systems and different working conditions, the results obtained from traditional simulation test method were often qualitative only, and couldn't be used to the designs of tribological system and practical engineering applications. There is a need to seek new ways and means of in-depth study of the wear quantitative law ,otherwise the fundamental breakthrough of the prevention and control of the wear could not be achieved. The tribological simulation research of the typical pin on disc sliding wear test system was carried by the adoption of computer technology and mathematical analysis methods, with a view to provide a new wear analysis method and the corresponding wear simulation model and to achieve simulation of the basic tribological contact problems and the wear problems.The content and results of this thesis were as follows:(1) The materials of 45 steel commonly used as mechanical parts was selected as wear specimens and the pin on disc sliding wear tests were carried on the MMW-1 vertical universal friction and wear test machine. By changing the load, speed and heat treatment state (hardness), the effect laws on wear of . these parameters were obtained(2) The wear simulation model including multiple parameters was established based on the experimental data and theoretical analysis. The parameters of the model were determined by the test data and to and the model was verified by the test data and the results showed that the simulation model could reflect the basic relationship between input and output of the pin on disc dry sliding wear test.(3) The contact stress theoretical calculating model of the pin on disc was deduced on the basis of the theoretical analysis of contact characteristics and contact stress calculation of the frictional couple. The two-dimensional and three-dimensional contact stress simulation analysis of the pin on disc contact couple were carried by the ANSYS software. The finite element simulation analysis results showed that the interface contact pressure distribution was uneven, contact pressure was small in the interspace of the contact interface and was big among the edge of the contact interface the small, the contact pressure peak reached 2.786 times of the load. The numerical value and conformation of the contact stress field arised great changes when the contact of Pin on disk was changed from static to dynamic state. The calculation results of three-dimensional and two-dimensional model were similar, only a small amount of change in value. The analysis results showed that ANSYS finite element method could be used to simulate the ideal contact state and it facilitated the analysis of stress state and friction and wear mechanism of the pin on disc from an intuitive view.(4) The theoretical modes of pin-on-disc specimens friction surface temperature and temperature field distribution were established through the test conditions analysis of the pin-on-disc friction couple, the friction surface temperature and temperature field distribution of 45 steel pin specimen was calculated by theoretical modes. Friction surface temperature fields were simulated also by finite element method. The calculating results of one-dimensional steady-state temperature field theoretical model of and two-dimensional steady-state differential model were same. The credibility of one-dimensional model of steady-state was further validated by the two-dimensional and three-dimensional transient finite element model results. The finite element analysis results showed that the friction temperature field of the pin on disc friction couple reached steady-state about 40s after start sliding in the sliding wear process, the steady-state temperature rise behaved basically linear distribution along the pin axis direction, the maximum temperature rise of the contact surfaces of the two-dimensional and three-dimensional finite element model are basically the same;(5) One dollar non-linear regression model, multivariate nonlinear regression model and BP neural network model were respectively studied for the pin on disk dry sliding wear rate data. The analysis results of different types of one dollar non-linear regression, multivariate nonlinear regression model showed that the forecast effects of the index regression model were the best. It was found that the forecast effects was the best when the number of points in hidden layer was seven by comparing forecast results the different number of points of hidden layer of the network model, accordingly the structure of the network model and specific parameters were determined. The regression model and BP network model all could be used to predict the pin on disk dry sliding wear rate, but the BP model forecast were more accurate.