DEM simulation of the powder application in powder bed fusion

TL;DR

This paper uses DEM simulations to analyze how inter-particle forces like adhesion and van der Waals influence powder packing density in powder bed fusion, aligning simulations with experimental data.

Contribution

It demonstrates the importance of including both adhesion and van der Waals forces in DEM models for accurate powder packing predictions.

Findings

Quantitative agreement with experimental packing densities

Adhesion and van der Waals forces significantly affect packing behavior

JKR model effectively captures adhesion effects

Abstract

The packing behavior of powders is significantly influenced by various types of inter-particle attractive forces, including adhesion and non-bonded van der Waals forces [1, 2, 3, 4, 5, 6]. Alongside particle size and shape distributions, the inter-particle interactions, in particular frictional and adhesive forces, play a crucial role in determining the flow behavior and consequently the packing density of the powder layer. The impact of various types of attractive forces on the packing density of powders with different materials and particle size distributions remains largely unexplored and requires further investigation. Accurately comprehending these effects through experiments while considering specific particle size distributions and material properties poses significant challenges. To address these challenges, we employ Discrete Element Method (DEM) simulations to characterize the packing behavior of fine powders. We can demonstrate quantitative agreement with experimental results by incorporating the appropriate particle size distribution and using an adequate model of attractive particle interactions. Furthermore, our findings indicate that both adhesion, which is modeled using the Johnson-Kendall-Roberts (JKR) model [7], and van der Waals interactions are crucial factors that must be taken into account in DEM simulations.