Research On Preparation And Heat Transfer Of Graphene Composites

With the improvement of integration, working frequency, and density assembly of electronic components. The power of electronic components are also constantly improved, so that a serious fever may badly hurt the function and life of electronic products.This give higher requirements to the thermal design of electronic products. Thermal Interface Materials is the material which exists between electronic components and the radiator. The purpose of join interface material is filling the gap between the interface,reducing the contact interface between the contact thermal resistance,to improve the efficiency of heat transfer, make the radiator to run efficiently.The research purpose of this paper is to prepare high thermal conductivity thermal interface materials, reduce the interfacial thermal resistance, make the heat generated by the electronic components can be successfully conducted to the radiator.Maintain stability and efficient operation of electronic components. In order to solve this problem, the research content is as follow:1. Graphite oxide is prepared by the method of hummers, then the thermal expansion of graphene. Also, graphene and alumina are doped into the epoxy resin prepare composite materials which hold high thermal conductivity.Both thermal conductivity and electrical resistivity of the compersite materials are measured.2.In this study, the interface thermal resistance of two specimens which add thermal interface material is measured by the interface thermal resistance test equipment. Found that:(1) Graphene, alumina doped into the epoxy resin respectively, can improve the thermal conductivity of composite materials, also reduce the size of the interface thermal resistance between the two specimens contact interface. Graphene and alumina are treated with coupling agent can improve the composite thermal conductivity, reduce the interface thermal resistance. When the mass fraction of Graphene is 10 wt % and alumina is 20 wt %, the thermal conductivity of composite materials is 6.2 W/m· K, the interface thermal resistance between the contact is 1× 10-5m2K/W.(2) When the load is a constant, the interface thermal resistance of the composite are decreases gradually with the increase of heating temperature. At the same time, for the same kind of material, the interface thermal resistance sharply reduced with load pressure trend, when the stress reaches a certain degree, the interface thermal resistance tends to be stable.3.The graphene/alumina/epoxy resin composite thermal interface material is used in the LED packaging, also do experiments and simulation of microchannel radiator cool the LED. Through this study, the composite thermal interface materials can be a very good transfer to heat, ensure the LED junction temperature under the allowable temperature.Also the result of the experiment and simulation error analysis, the maximum error is6.5%.