Effects of infill temperature on the tensile properties and warping of 3D-printed polylactic acid

Although extensive research has been carried out on the effects of temperature on the properties of parts by fused filament fabrication, no study considered the opportunity to use different temperatures and cooling strategies for the contour and the infill region. The purpose of this investigation is to explore such an opportunity through an experimental campaign on polylactic acid. Specifically, the variations in tensile properties and warping occurring with different infill temperatures and cooling methods are documented. The results demonstrate that diversifying process parameters used for the contour and infill of the part allow for significant improvements in mechanical properties without affecting the distortion of the manufactured samples. This result can be achieved by either increasing the nozzle temperature or switching off the cooling fan during infilling.