Discrete Element Modeling (DEM) simulations of powder bed densification using horizontal compactors in metal additive manufacturing

Abstract

Efficient packing of the powder bed plays a key role in ensuring high quality of parts printed with Powder Bed Fusion (PBF) based additive manufacturing technologies. This paper presents simulations and analysis of a new technique based on horizontal compactors for improved densification of the spread powder layer. Discrete Element Modeling (DEM) based simulation of this technique shows much improved bed densification and force reduction on the layer underneath, thereby contributing to improved part quality. Results are found to be in excellent agreement with past work. Simulations predict the void fraction distribution as a function of various process parameters. Simulations are carried out to understand the effect of number of particles on stresses acting on the previously printed layer. The technique discussed here is a general one, and may also help analyze other powder-based additive manufacturing processes such as selective laser sintering and binder jetting.