The Additive Manufacturing (AM) industry continues to seek ways of reliably identifying powders that will deliver printed components with the required mechanical properties. There is widespread understanding that such specifications necessarily include multiple chemical and physical parameters. Physical specifications can be further sub-divided into particle variables, notably particle size and increasingly particle shape, and bulk powder properties such as density. Determining the bulk powder properties that are most relevant with respect to quantifying the spreading and packing behaviours that define AM performance remains an ongoing focus.
A new study from De Montfort University adds further weight to the case for including dynamic, bulk, and shear properties in AM powder specifications. In this work an advanced powder tester (FT4 Powder Rheometer®, Freeman Technology) was used to establish robust correlations between powder properties and the mechanical characteristics of polyamide (PA12) samples printed by Selective Laser Sintering (SLS). The results demonstrate how with the appropriate powder testing it is feasible to predict print quality from powder properties thereby moving away from a trial-and- error approach to powder selection.