Material Extrusion Additive Manufacturing and Experimental Testing of Topology-Optimised Passive Heat Sinks Using a Thermally-Conductive Plastic Filament

Abstract

This paper presents an experimental study of topology-optimised passive heat sinks produced in a thermally-conductive plastic using material extrusion additive manufacturing. The thermal performance of the filament is investigated through test printing, thermal conductivity testing and scanning electron microscope imaging. Topology optimisation is used to generate novel heat sink designs for passive cooling through natural convection. The optimised designs are complex and are printed using soluble support materials. The measured anisotropic thermal conductivity of the layer-by-layer additively manufactured specimens is included in the topology optimisation process to design heat sinks specifically with the chosen filament and process in mind. It is shown that when taking the material anisotropy into account, the topology-optimised heat sinks deliver up to 10-20\% reduction in thermal resistance compared to a reference straight-fin design.

Keywords: Material Extrusion, topology optimisation, thermal conduction, heat sink