The Study On Fabrication And Properties Of High Strength And High Thermal Conductivity Graphite/aluminium Composites Material

Natural flake graphite not only has the properties of high thermal conductivity,low thermal expansion,low density,but also has the advantages of low cost and high storage.It is a kind of high commercial value of electronic packaging composite material.At present,the most important concern in electronic packaging composites is the aluminum matrix metal composites.Graphite / aluminum composites are the research hot spots at present,but their low mechanical properties have been restricting its application and future.This paper mainly uses the method of electroless plating Cu and salt bath plating Ti to modify the surface of natural flake graphite,enhance the strength of the graphite sheet and improve the interface bonding of graphite / aluminum composite,so as to improve the comprehensive properties of bending property and thermal conductivity of the composite.A high thermal conductivity and high strength composite material with a bending strength of more than 100 MPa and a X-Y surface thermal conductivity greater than 400 W/(m K)has been successfully prepared.It can be used as an excellent new type of electronic packaging material and used in the application of heat management.The main contents are as follows:(1)The surface of graphite was modified by the method of salt bath plating Ti and electroless plating Cu,and the influence of coating element and coating process on the surface bonding of graphite / aluminum composite was studied.(2)Graphite / aluminum composites were prepared by vacuum hot pressing in powder metallurgy,and the preparation process of materials and the influence of the reinforcement on the properties of the composites were investigated in detail.(3)To test the thermal conductivity and bending resistance of the graphite / aluminum composites,the material composition,the interface morphology,the reinforcement arrangement and the density of the graphite aluminum composites were analyzed.The influence of the graphite surface coating on the properties of the composites and the reasons were investigated in detail.