Isotropic thermal expansion in anisotropic thermal management composites filled with carbon fibres and graphite
Language
en
Article de revue
This item was published in
Journal of Materials Science. 2018, vol. 53, n° 15, p. 10910-10919
Springer Verlag
English Abstract
Light materials with high thermal conductivity and low thermal expansion have a wide application potential for the thermal management of high-performance electronics, in particular in mobile and aerospace applications. We ...Read more >
Light materials with high thermal conductivity and low thermal expansion have a wide application potential for the thermal management of high-performance electronics, in particular in mobile and aerospace applications. We present here metal matrix composites with a mixture of graphite flakes and pitch-based carbon fibres as filler. The production by spark plasma sintering orients the filler particles on to a plane perpendicular to the pressing axis. The obtained materials have lower density than aluminium combined with a thermal conductivity significantly outperforming the used metal matrix. Depending on the ratio of the filler components, a low thermal expansion along the pressing direction (high graphite flakes content) or across the pressing direction (high carbon fibre content) is achieved. For a 1:3 ratio of carbon fibres to graphite, we measured an isotropic reduction of the thermal expansion of the matrix by up to 55%. We present a detailed characterisation of composites with two aluminium alloys as matrix and an overview of the properties for six different metal matrices including magnesium and copper. With the goal of a technical application, we show that the described properties are intrinsic to the material compositions and are achieved with a wide spectrum of production methods.Read less <
Origin
Hal imported