Characterisation of carbon fibre-reinforced polyamide manufactured by selective laser sintering

Polymers and reinforced plastics are employed in various load-bearing applications, from household objects to aerospace products. These materials are light, strong, and relatively cheap but can be difficult to form into complex geometries. However, the development of additive manufacturing processes has made it easier to manufacture reinforced plastics in complex shapes. The aim of this work was to study the internal features and mechanical properties of carbon fibre-reinforced polyamide (CF/PA12) fabricated with the additive manufacturing technique of selective laser sintering. The test specimens were studied using computed tomography to analyse the internal geometry, and the material proved to be highly porous. Moreover, the test specimens revealed an internal layered structure, which was found to have a great effect on the tensile properties of the material. The results highlight that there is room for further optimisation of the manufacturing parameters for CF/PA12, because the layered structure makes it challenging to design end user parts with acceptable mechanical properties.