Commercial powder bed fusion additive manufacturing systems use recoaters for the layer-by-layer distribution of powder. Despite the known limitations of recoaters, there has been relatively little work presented on the possible benefits of alternative powder delivery systems. Here, we show the use of a technology using simple vibration to control the powder flow for powder bed additive manufacturing. The capabilities of this approach are illustrated experimentally using two very different powders; a `conventional gas atomized Ti-6Al-4V powder designed for electron beam additive manufacturing and a water atomized Fe-4wt%Ni alloy used in powder metallurgy. Discrete element modelling is used to reveal the mechanisms controlling the dependence of feed rate on feeder process parameters and to investigate the potential strengths and limitations of this approach.
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