Spreadability Of Metal Powders: Combining Powder Characterization And DEM Simulations

A good prediction of powder spreadability is essential in powder bed-based additive manufacturing to guarantee the quality of the built parts. In this study, we combine powder characterization in a rotating drum geometry (GranuDrum, Granutools, Belgium) and layer quality evaluation in an instrumented test bench (LEM3, France). The results demonstrate the strong link between powder cohesiveness and spatial irregularities of the produced layers. The experimental study is complemented by a DEM investigation, in which the bed and recoater configurations are similar to the experimental ones. The DEM simulation allows investigating more deeply the spreading mechanisms by giving access to measurements that are difficult to obtain experimentally. Especially, we study the link between the strength of the cohesive forces acting between the particles and its consequences on the layer irregularity.