SBIR Phase I: Ultra High Thermal Conductivity Aluminum/Graphite Composites from Recovered Scrap Graphite and Low Cost Natural Graphite

This Small Business Innovation Research (SBIR) Phase I project will use recycled or natural graphite to develop low cost graphite/aluminum composites with high thermal conductivity for electronic thermal management applications. Highly conductive graphite flakes randomly dispersed at ~75 volume percent (v/o) into Al matrix with zero interface resistance is calculated at a conductivity of 800 W/mK, (2x copper). Zero interface impedance is due to the formation of a SiC reaction layer at the interface during infiltration of high v/o graphite preforms. Achieving the highest possible thermal conductivity using flake graphite will involve developing near isotropic graphite flake preform architecture and a material with controllable thermal expansion. The primary challenge in the proposed work will be to achieve random distribution of flakes having access to molten Al-Si during infiltration to enable the desirable SiC interface reaction. Today's products, for cellular phones to sophisticated imaging satellites require high performance materials that keep pace with emerging market demands. Consumer electronics and microelectronics packaging systems are smaller, hotter and must provide increasing functionality in less space. Thermal management is critical technology for future electronics systems. A major goal of this research then is to replace copper and other legacy materials with lightweight, low-cost, highly conductive Al/graphite flake composites.