| At present, oil-based lubricant has been widely used in modern field of lubrication.But with the increase of the people environmental protection consciousness, water isexpected to exchange oil to achieve the effective lubrication for machine. It has becomean important research direction in the tribology research. Water-based lubricant has theadvantages of low cost, convenient storage and transportation, not burning. Starting inthe1990s, water-based lubricant has been widely used in the field of metal processingand hydraulic transmission. However, viscosity of water is very low, which leads to thatthe water-based lubricant is difficult to form a complete lubrication film in the contactarea. So it is generally believed that the oil lubrication performance is better than waterlubrication. Adding the water soluble lubricant additives in the water could improve thetribological properties of water. The water soluble lubricant additives reported so far arebased on the oil-based antifriction and anti-wear additive by adding water-soluble groupto molecular structure to improve its solubility in water. As a consequence, the use ofthis kind of additives may cause certain pollution to the environment. Therefore, thestudy of new type water soluble lubricant additives is becoming more and moreimportant in recent years. This paper mainly relates to the field of work. In this thesis,we try to use three kinds of compounds those are polyvinylpyrrolidone, Tween-80andglycerol which were non-toxic, biocompatible and water-soluble as water-basedlubricant additives. We systematically study wear resistant and anti-wear characteristicsof water-based lubricant under various lubrication conditions. Experiment has madesome progress and the resultd are as follows.(1) This paper researched the polyvinylpyrrolidone (PVP) aqueous solution oftribological properties on the friction and wear tester. Experiment found that it hasexcellent lubrication performance in the low speed and low load condition. Adding PVPto water improved the lubrication performance of the water. So PVP is an efficaciouslywater-based additive. It is also found that adding salt ion in PVP solution can be futherimproved lubricating performance of the PVP solution, and the more salt concentrationincreased in a certain concentration, the more lubrication performance enhancements. (2) This paper researched the tween-80aqueous solution of tribological propertieson the friction and wear tester. Experiment found that tween-80aqueous solution at5%concentration has the better lubricity; when the concentration of tween-80aqueoussolution is1%, the friction coefficient on steel-steel friction pair can be less than0.1inthe load of4N. The extreme pressure performance of tween-80aqueous solution istested by using four-ball friction tester. It is found that it can still lubrication effectivelyunder the high load.(3) This paper researched the glycerol aqueous solution of tribological propertieson the friction and wear tester. Experiments found that glycerol aqueous solution hasexcellent lubrication performance on glass substrates, and the lowest friction coefficientcan reach0.005, i.e. superlubrication. Two materials (glass, steel) are chosen assubstrates for coating TiO2film. It was found that the TiO2film has certaincharacteristics using glycerol lubrication; it can be more closely combined on thesurface of steel to reducing friction and wear after UV irradiation.Three kinds of water-based lubricant those are polyvinylpyrrolidone, Tween-80and glycerol are tested in this thesis. Lubrication mechanism of aqueous solution areexplored by using the friction and wear tester, scanning electron microscopy and contactangle measurement in order to provide experimental support for the further explorationof the water-based lubricant. |
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