Preparation And Properties Of Dispersion Copper-MoS₂Composite Material

With the development of electronic、 mechanical， aeronautic andaerospace industry, it is required that develop copper matrix composite withnot only high electrical conductivity， thermal conductivity， but alsoexcellent mechanical properties and wear-resistant.In this thesis， the dispersion Copper-MoS₂composite material wasprepared by powder metallurgy. The different methods of preparation ofpowder were investigated, and the purpose was to have the best performancematerial which was produced with the best technology. SEM， XRD， DSC，TEM and other detection methods were used to analyze the structureproperty of material. Ultimately, the composite material was used in thecurrent-carrying wear experiment to analyze the change rule of frictioncoefficient and wear rate. The works include the following aspects：1. Two different technology of ball milling and conventional mixingwhich affect the property of composite material were researched. Afterpressing and sintering, the dispersion Copper-MoS₂composite material withthe conventional mixing method had the better value of the density、hardness and conductivity.2. After analyze the change rule of powder pellet in ball milling,composite powder gathered plenty of distortion energy， defect energy andsurface energy which was stored in the surface of powder particle afterrefining、 grain boundary and defect. The energy would affect the structureproperty of composite material.3. The phase transition in sintering of composite material was analyzedby XRD and DSC detection methods. The ingredient of MoS₂was changedand two new phases Cu_1.84Mo₆S₈and CuMo₂S₃were produced after the reaction in sintering. This chemical reaction was endothermic reaction, thetemperature was532℃.4. In the process of composite material was prepared by hot pressingand sintering technique, two different materials contained different massfraction of MoS₂were researched. The research discovered the density，tensile strength and the conductivity of the material were declined and thehardness was little changed with the increase content of MoS₂.5. Two different technology of pressing were researched. The researchdiscovered composite material was prepared by hot pressing and sinteringtechnique which had the better performance than cold pressing.6. The test specimens which were produced by hot pressing andsintering technique were used in the current-carrying wear experiment. Theresult showed that the3%（wt） MoS₂composite material had the betterwear-resistant, the friction coefficient and wear rate of3%（wt） MoS₂composite material were less than1%（wt） MoS₂composite material...