| Based on the basic principles of polymer material and tribology the comprehensive investigation on the tribology behavior of polymer-matrix composite material has been made about solid lubricant used in the embedded bearing for hydraulic generator. After looking up a large amount of native and foreign information, the materials used in the experiment were as follows: PTFE base, graphite filler, molybdenum disulfide filler, copper powder filler, carbon fiber and so on. The experimental method is that the formula was designed according to uniform experimental method, the relationship between formula and frictional property was found with spline function and then the representative test points were chosen from fitting curve to make verification test for optimization. The preparative technique of solid lubricant is cold-press sintering method.The micro-structure , friction surface, lubricant transfer film surface of base material was characterized by SEM; XRD was used to do phase analysis. The degrees of crystallinity of pure PTFE under the different conditions of water cooling, air cooling and furnace-varying cooling were made comparison by XRD. The thermal stability of pure PTFE and solid lubricant was analyzed by DSC-TG; The composition and valence state of elements in the surface of carbon fiber ,solid lubricant before and after friction test and lubricant transfer film were characterized by XPS; The frictional property of solid lubricant was tested by pin and disk test rig . The frictional wear property of solid lubricant between embedded bearing sleeve and steel axle friction pair ring was tested by special simulate test machine, The hardness of solid lubricant was tested by PM; The compression strength of solid lubricant was tested by material test machine.The results indicated that the dimension, shape and purity of base material could meet the functional demand of solid lubricant; The thermal decomposition temperature of PTFE resin exceeds 400 C, but organic and inorganic packing filler added in PTFE made the water absorption rate of composite material increased, melting temperature and decomposition temperature decreased ,in the meanwhile oxidative decomposition reaction was accompanied; Polar groups such as C=O,C-O-C and so on in the carbon fiber surface is advantageous to increase compatibility with other components and interlayer shearing strength; Uniform design experimental method could help to find the relationship between formula and frictional property by relatively small tests .The developing trend ofeach formula's friction coefficient could be showed by fitting curve; The frictioncoefficient with no copper powder or graphite in formula was relatively big .This fact showed that copper powder and graphite should be used cooperatively; It was found that when the ratio of copper powder to graphite by weight is 15:60,30:30-40 and 60:15-30 respectively, the friction coefficient was relatively small. The degree of crystallinity of pure PTFE reached maximum by air cooling and the abrasion loss also reached maximum among three ones; At the same time, the abrasion loss of solid lubricant sample was also the biggest among three ones; when solid lubricant matched with 45# steel axle or GCrl5 steel axle, lubricant transfer film could be formed on metal surface, thus direct contact between the surface of metal friction pair rings was reduced. Their working life was elongated extremely; There was mainly much graphite, a little PTFF, MoO3, FeSO4, CuS and so on in lubricant transfer film. Sintering or friction all brought about chemical change in the surface of solid lubricant and the change of valence state of Mo, S, Fe and so on; The micro-hardness of pure PTFE was minimum and the surface-hardness of solid lubricant was increased with the increase of additional packing filler in formula; The compressive strength of pure PTFE was minimum and its compressive strength could be increased notably by adding organic and inorganic filler. But not more additional amount, more notable increase of compre...
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