Tribological Study Of UHMWPE Based On Numerical Technology

Thermoplastics, such as UHMWPE, have been successfully used in biomedicine, MEMS, ocean engineering, foodstuff process, spinning mechanism, chemical mechanism and so on. But, there are some insurmountability problems in processes of thermoplastics application, for example, they are sensitive to temperature elevation caused by friction heat; their strength, deformation and creep are all affected by temperature. Even so, they cannot be replaced in some case for their other special properties needed by some systems, hence tribological problems of thermoplastics become basic research project with important scientific meaning.Supported by the Natural Science Foundation Committee of China (50175041), the main research work in the present dissertation involves:(â… )The background and meaning of the research were discussed. The way to solve the problem was confirmed.(â…¡) Based on the internal comparability of macro topography and microcosmic real surfaces, DEM was introduced to tribology and used to describe microcosmic real surface. So a new way to describe tribological surfaces was supplied. Based on the method of science visualization, the technique of two-dimension image identifying was taken as the point of departure and software for obtaining height data of three dimension surfaces from two dimension height images was built. The problem to get the height data of three-dimension model was solved. The practicability and veracity of this method was proofed by the reconstruction of surfaces measured by AFM, Taylor Hobson.(â…¢) To solve the problem that parameters used in common contact model are relatively simple and not suitable to studies on friction and contact of thermoplastics, the real deformation of UHMWPE under conditions of room temperature and alternating temperature was respectively tested. Thus a real stress-strain curve and a strength-temperature curve were obtained. Both curves were used to build a pole contact model based on real compressive deformation law. Then the model could more exactly and more practically show the compressive deformation regular and friction heat effect regular of UHMWPE during friction and contact processes. The calculating method and program of the contact simulation were brought forward. And furthermore, the software...