High Thermal Conductivity and Mechanical Properties of Nanotube@Cu/Ag@Graphite/Aluminum Composites

Weak interfacial bonding and the agglomeration of reinforcements are critical challenges for the expected performance in thermal management materials, hindering the extensive application of aluminum matrix composites. In this work, Cu particles, nanotubes, Ag-coated graphite flakes and films, urea, and starch were mixed together to fabricate porous preforms, which then were infiltrated by vacuum gas pressure at 720 °C. The effects of graphite film thickness on the microstructure and properties of thermal conductivity (TC) and coefficient of thermal expension were investigated. The nanotube@Cu/Ag@graphite/aluminum composites exhibited a high TC of 451 W/mK and excellent bending strength of 74 MPa, which were approximately increased by 48.8% and 126%, respectively, as compared with the samples without graphite film.