Improvement in Mechanical and Thermal Properties of Graphite Flake/Cu Composites by Introducing TiC Coating on Graphite Flake Surface

Abstract

In this work, TiC coating was successfully deposited on a graphite flake surface via molten salt technique, for the purpose of promoting the interfacial connection between Cu and graphite flake. Vacuum hot pressing was then employed to prepare TiC-coated graphite flake/Cu composite. The results indicate that introducing TiC coating on graphite flake surface can evidently reduce the pores and gaps at the interface, resulting in a significant improvement on the bending strength. When the TiC-coated graphite flake content is 60 vol%, the bending strength is increased by 58% compared with the uncoated one. The coefficient of thermal expansion dropped from 6.0 ppm·K−1 to 4.4 ppm·K−1, with the corresponding thermal conductivity as high as 571 W·m−1·K−1. The outstanding thermal conductivity, apposite coefficient of thermal expansion, as well as superior processability, make TiC-coated graphite flake/Cu composite a satisfactory electronic packaging material with vast prospect utilized in microelectronic industry.

Kinetic Models for the in Situ Reaction between Cu-Ti Melt and Graphite

“…The preparation of this composite material can be divided into two ways. The first approach is to prepare TiC x powder, and then prepare MMCs by powder metallurgy [13,[17][18][19][20], or to mix TiC x powder into a metal solution and cast it [21]. The second method is to combine the preparation of TiC x powder and the composite process.…”