Investigation of the Influence of Printing Parameters on Thermal Shrinkage Behaviour in an Additive Extrusion Process

Abstract

Additive extrusion is a process known for its orthotropic outcoming in terms of material behaviour. While said behaviour has already been intensively assessed for mechanical properties, the process’ influence on thermal shrinkage is yet accurately to be examined. This paper contributes to the assessment of the thermal shrinkage behaviour caused by different printing parameters used in the additive extrusion process. On coupon level, specimens are printed, incorporating fibre-optical sensors. These sensors allow for an in-process assessment of thermal shrinkage over the whole specimen length. While modifications of printing speed and layer height show a clear picture in their influence on thermal shrinkage, the influence of the extrusion factor does not seem to be clearly quantifiable. The results gained in this feasibility study may help to understand thermal shrinkage and therefore to predict processinduced deformations in additive extrusion processes. Other use cases can potentially be seen in mono-material tunable thermal expansion structures or the adjustment of 3D printed membrane-type resonators.