Discrete element simulations of powder-bed sintering-based additive manufacturing

Additive manufacturing (AM) is the processing of jointing raw materials to make objects, usually in a layer-by-layer fashion, from 3D data. It has become a promising tool for a wide range of applications in recent decades. Nevertheless, qualification and certification remains the major challenge for the AM. One possible approach to address this challenge is using computer simulations as an examination and prediction tools. In this work, we present a prototype discrete element model aimed to replicate one of the most common AM process, the powder-bed sintering. This DEM model is designed to incorporate heat conduction, phase transformation and inter-particle sintering that mimics the powder-bed sintering-based AM process. The DEM-based thermal conductance and bond neck growth models were verified against a closed form analytical solution and the Coblenz model, respectively. Numerical simulations are provided to examine the mechanical properties of the printed objects. (C) 2017 Elsevier Ltd. All rights reserved.