Preparation,Properties And Model Of Graphene And Carbon Nanotube Based Thermal Conductive Lubricants

Lubricating oil can be used in different environments for lubrication.In order to make it have more functions and be used in more severe working conditions,various additives are often added in lubricating oil.In recent years,heat conducting lubricant additives have received more and more attention.It is particularly critical to add additives with good anti-wear and anti-friction properties and thermal conductivity when they are used in the environment of severe wear and high temperature.At present,the research shows that adding nanoparticles can improve the lubrication and heat transfer performance of traditional lubricating oil.In view of the excellent tribological properties and heat transfer performance of nano lubricating oil,it is necessary to analyze and study its thermal conductivity and heat transfer performance in the process of friction in addition to the study of its tribological performance.Due to their excellent mechanical properties,graphene and carbon nanotubes are widely used as lubricating additives,which have excellent performance in improving friction reduction and anti-wear of lubricating oil.In addition,graphene and carbon nanotubes have larger conjugated systems,which can be used as thermal conductivity additives.Ag nanoparticles have the potential to provide excellent electrical conductivity when used as thermal fillers.However,due to its easy agglomeration,high weight and high cost,metal nanoparticles were used as coatings to load on the surface of carbon nanotubes and graphene to prepare Ag/CNTs and Ag/rGO nanocomposites.The prepared nanocomposites can give full play to the advantages of high aspect ratio between carbon tubes and go,and enable metal nanoparticles to effectively participate in the conduction network and enhance the thermal conductivity of the whole system.As a high thermal and conductive composite filler,the nanocomposite material maintains a high aspect ratio throughout the whole process,which enables the composite material to form an ultra-strong thermal and conductive network under a very low volume load.In this paper,by adding carbon nanotubes of different diameters,nanoparticles of different particle sizes and graphene into dimethylsilicone oil,the effects of different structures on lubrication,thermal conductivity and electrical conductivity of lubricating oil were investigated,and the thermal conductivity model was constructed.The main research contents of this paper are as follows:1)In this study,Ag/CNTs and Ag/rGO were prepared and characterized.2)Dimethyl silicone oil was used as the base oil,the thermal conductivity and electrical conductivity of carbon nanotubes with different contents and different diameters were investigated.3)Dimethyl silicone oil was used as the base oil to guide the design experiment from the viewpoint of classification.The thermal conductivity and electrical conductivity of carbon nanotubes,carbon nanotube-loaded silver nanocomposites and silver nanoparticles were compared.4)Based on the analysis of experimental results,this study further analyzes the data,explores the thermal conductivity mechanism,and builds a thermal conductivity model.5)The heat transfer process of the prepared nanocomposite as an additive and the heat dissipation process of the commercially available Dow Corning thermal grease were compared by temperature change by FTIR420 infrared thermal imager.6)This paper explored the tribological properties of Ag/CNT nanocomposites and Ag/rGO nanocomposites using a four-ball friction testing machine and a CSM Pin-on-disk tribometer.