Fabrication of graphite film/aluminum composites by vacuum hot pressing: Process optimization and thermal conductivity

Effective thermal management is becoming increasingly important for high power density electronic devices, which requires materials with high thermal conductivity. A novel graphite film/aluminum composite material with ultrahigh thermal conductivity was fabricated by vacuum hot pressing process to meet this requirement. The effects of fabrication parameters on microstructures and thermal conductivities of these composites were investigated. As a result, the composites with graphite volume fraction of 17.4-69.4% sintered at 655 °C/45 MPa for 100 min exhibit in-plane thermal conductivities of 380-940 W/mK, over 90% of the predictions by rule of mixture. These composites possess higher in-plane thermal conductivities than graphite flake/aluminum composites due to well-controlled graphite orientation and fabrication parameters, which indicates that these composites are promising materials for effective thermal management.