A review on thermophysical properties of flexible graphite

Abstract

Flexible graphite (FG) is the last stage of compression of expanded graphite. Natural and highly crystalline graphite flakes are expanded and rolled together without any binder in order to shape foils of different thicknesses and densities. The result is an anisotropic but highly conductive material, with low strength and stiffness compared to common graphite, but gathering a collection of different peculiar properties. About mechanical field, FG is mostly used in sealing and gasketing applications due to its resilience and capability of dissipate energy during vibration. It also shows high resistance against chemical agents and can retain its structural integrity at temperature up to 2500℃ in inert atmosphere. All the mechanical, electrical and thermal properties are strongly affected by the inherent anisotropy that make it exploitable in thermal cooling, interface insulation, electromagnetic shielding and in electrical conduction components such as fuel cell electrodes. In this work the manufacturing process is summarized together with the effect of density on strength and modulus and the experimental results found in literature among anisotropy, stiffness, thermal and electrical conductivity, specific heat and thermal expansion are reviewed together with some modeling approaches.