The Study Of Self-lubricating Covered Model At Elevated Temperature

In the thesis, a new covered model is developed for analyzing self-lubricating mechanism of sweat gland self-lubricating composites at high temperature based on the micro-structure of the material. Tribological behaviors and self-lubricating mechanisms are also studied. The main achievements are as follows:1. New sweat gland self-lubricating composites are produced by pressureless infiltration technology with micro-pores ceramic as matrix and soft metal lubricants as additives. The microstructure of the new material is studied. Several methods are adopted to solve the problems appeared in the process of infiltration.2. Anew covered model is presented for analyzing self-lubricating mechanism of sweat gland self-lubricating composites. In the model, the frictional heat and the thermal stress coupled field are simulated by a numerical method. The effects of friction coefficient and out layer material properties on the diffusion of lubricating elements are investigated in the paper.3. The tribological behaviors of sweat gland self-lubricating composites are studied in detail. Results indicated that the friction coefficient of the composites is greatly decreased by infiltrating soft metal lubricants into micro-pores matrix. The friction and wear properties of the composites are affected by temperature, coupled material and loads.4. A model of forming solid lubricating film is established by analyzing the forming process of self-lubricating film. Elements of solid lubricating film are analyzed by EDS and the results indicated that there are many soft metal elements in the solid lubricating film. The stress in solid lubricating film is analyzed in theory and calculated with FEM.