Heat Transfer Performance Study Of Reduced Graphene Oxide/Copper Composite Thermal Interface Materials

The advancement of science and technology drives the development of artificial intelligence.The carrier of artificial intelligence is electronic devices.Any electronic device will generate heat when it is working,and the accumulation of heat will eventually affect the working efficiency of electronic products.Therefore,solving the heat dissipation problem of electronic products is one of the key factors for technological progress.The emergence of graphene has brought infinite possibilities to the development of modern science and technology.Its excellent thermal conductivity and excellent physical and chemical properties make it play a huge role in the field of heat dissipation materials.Graphene has been extensively studied in various fields,so there are many preparation methods.Among them,the redox preparation process is simple,low-cost,safe and efficient,and is currently one of the more common methods for preparing graphene.In this paper,an improved Hummers method is used to prepare graphene oxide,and reduced graphene oxide/copper composite materials are prepared by electrophoretic deposition;the effects of suspension concentration,deposition voltage,time,temperature,and p H on the film forming properties of composite materials during electrophoretic deposition are studied.Influence;explored the influence of sintering temperature,pressure,temperature rise rate and holding time on the thermal conductivity of composite materials during sintering.The microscopic morphology of the composite material was observed and analyzed by the SEM scanning electron microscope,the thermal conductivity of the composite material was tested by the Hotdisk thermal constant analyzer,the tensile strength of the material was tested by the dynamic mechanical analyzer,and the material's strength was tested by the thermomechanical analyzer.Thermal expansion coefficient.The experimental conclusions obtained are as follows:(1)During electrophoretic deposition,the deposition voltage,time,and temperature have a greater impact on the film-forming properties of the composite material,followed by the solution concentration and p H.The optimal process parameters are determined,that is,the optimal deposition concentration is 2 mg/m L.The voltage is 25 V,the deposition time is30 s,the optimal temperature is around 30°C,and the overall solution p H is neutral.(2)Through the sintering treatment,the thermal conductivity of the composite material is increased from 415 W·m-1·K-1 when unsintered to 568 W·m-1·K-1.The sintering parameters are determined as follows: under a pressure of 30 MPa,Heat to 900°C at a temperature rise rate of 5°C/min in the low temperature stage and 10°C/min in the high temperature stage,cool with the furnace,and hold for 60 minutes before the temperature rise changes.(3)During the electrophoretic deposition process,the graphene oxide is originally reduced and deposited on the surface of the copper matrix.At the same time,the ionized copper particles are combined with the graphene and distributed between the graphene sheets to enhance the strength of the composite material;the composite material is further enhanced by sintering.Dense,thermal conductivity increases,and thermal expansion coefficient decreases.(4)The reduced graphene oxide/copper composite material enhances the thermal conductivity of the epoxy resin-based material from 0.18W·m-1·K-1 to 0.61W·m-1·K-1,an increase of 238.9%;the enhancement effect of multilayer graphene is more obvious,Increased by 450%;thermal conductivity first increased and then decreased with the increase of viscosity.