Advanced Characterisation of the Ageing Effects of Polymer Powders for Additive Manufacturing

Additive manufacturing (AM) technologies are rapidly advancing, with material characterization playing a key role in process optimization and new material development. This is especially true for polymer powder bed fusion (PBF), where nylon-12 dominates the market.

In PBF, unsintered powder acts as support and remains at elevated temperatures, often for hours, leading to thermal ageing. This ageing can alter material properties, affecting both processability and part performance. To assess these effects, we characterized aged polyamide (PA) powders, including filled and unfilled variants, and polypropylene (PP) using Differential Scanning Calorimetry (DSC), Rheology, and Gel Permeation Chromatography (GPC). Virgin materials were compared to aged powders.

This research demonstrates that powder ageing significantly alters material behavior, increasing elasticity and influencing powder application during the PBF process. The findings highlight the need to adjust processing parameters when using aged powders to maintain part quality and process efficiency.