The Study Of Preparation And Tribological Properties Of Highly Dispersible Molybdenum Disulfide

Friction and wear problems have been the main cause of energy consumption and material loss and the most effective approach to control or reduce friction and wear is to use a lubricant.With the increasing performance parameters of modern mechanical equipments,the traditional lubricating oil and its organic lubricant additives have not fully meet the performance requirements of the modern industrial production.In recent years,nano-tribology has gradually become a popular research field with the continuous development and application of nanotechnology.Adding some nanoparticles and its nano-composites or modified nano-materials into base oil significantly improves the anti-friction and anti-wear performance of the lubricating oil.Since then,the development of new-type nanometer lubricant additives has entered into a new stage.In this thesis,molybdenum disulfide?MoS₂?nano-materials were synthesized by hydrothermal method and surface modifications method.The morphology,size and structure of were analyzed by a various of modern analytical methods,and their were four-ball tribotester as the lubricating additive in different lubricants were evaluated at different concentrations and loads.The specific research contents and conclusions are as follows:The preparation of molybdenum disulfide coated carbon materials?MoS₂@C?and evaluation of tribology properties.MoS₂@C composite was prepared by hydrothermal method and the carbon layer coated on the surface of MoS₂ was about15 nm.The room temperature observation and the absorbance test proved that it has good dispersion stability as a lubricating additive in dibutyl phthalate base oil.The test results of the four-ball tribotester show that the MoS₂@C composite as a lubricating additive exhibits a certain anti-friction performance in dibutyl phthalate?DBP?,but the anti-wear performance is not obvious.In one word,the as-prepared MoS₂@C nanosheets can be solve the problem of dispersion stability in lubricating oil additives and the nano-material can be better used as a lubricating additive.Preparation of Polyethylene glycol400 grafted MoS₂?PEG-MoS₂?and evaluation of their dispersion stability tribology properties as the lubricating additive in Water and PEG400 lubricants.The room temperature observation,absorbance and zeta potential test proved that the PEG-MoS₂ hybrid has excellent dispersion stability in water environment and PEG400 lubricants.The results of the four-ball tribotester show that the PEG-MoS₂ possess excellent tribological properties in water and PEG400 lubricants.Results show that a layer of strongly polar organic molecules is present on the surface of the MoS₂ modified by Polyethylene glycol400.As a result,they can be effectively absorbed on the surface of the rubbing steel surfaces to provide excellent friction-reducing and antiwear performance.