Characterizing the Bulk & Flow Behaviour of LS Polymer Powders

The properties of laser sintering (LS) powders affect processability and the quality of parts manufactured. This study compared three different methods used to quantify both the static and dynamic powder properties – a Revolution Powder Analyzer, FT-4 Powder Rheometer and Hausner Ratio. The aim of the work was to identify the most reliable method to characterize powder properties in correlation to the dynamic conditions that occur during LS. The experiments focused on different particle size distributions of a cryogenically ground polyurethane powder compared to a standard polyamide 12 LS material, PA2200. The results have led to a deeper understanding regarding powder interactions and therefore serve as input for material design and quality assurance.