Abstract Selective Electron Beam Melting (SEBM) is a promising powder-based metallic Additive Manufacturing (AM) technology. However, most powder-scale modeling efforts are limited to single track process, while it is also difficult to experimentally observe the interaction between tracks and layers. In this study, we develop an integrated modeling framework to investigate the SEBM process of multiple tracks and multiple layers. This approach consists of a Discrete Element model of powder spreading and a Computational Fluid Dynamics (CFD) model of powder melting. These two models exchange 3D geometrical data as a cycle to reproduce the manufacturing process of multiple tracks along various scan paths in multiple powder layers. This integrated modeling approach enables further understanding of how current tracks and layers interact with previous ones leading to inter-track/layer voids. It also incorporates more influential factors, particularly the layer-wise scan strategy. The inter-layer/track voids due to the lack of fusion are systematically discussed in light of our simulation results which qualitatively agree with experimental observations in literature.

中文翻译：

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选择性电子束熔化中多层制造工艺的中尺度建模：层间/轨道空隙形成

摘要 选择性电子束熔化 (SEBM) 是一种很有前途的粉末基金属增材制造 (AM) 技术。然而，大多数粉末尺度建模工作仅限于单轨迹过程，同时也很难通过实验观察轨迹和层之间的相互作用。在这项研究中，我们开发了一个集成建模框架来研究多轨道和多层的 SEBM 过程。该方法由粉末扩散的离散元模型和粉末熔化的计算流体动力学 (CFD) 模型组成。这两个模型以循环的方式交换 3D 几何数据，以在多个粉末层中沿着不同的扫描路径重现多条轨道的制造过程。这种集成建模方法有助于进一步了解当前轨道和层如何与先前的轨道和层相互作用，从而导致轨道间/层间空隙。它还包含了更多影响因素，尤其是逐层扫描策略。根据我们的模拟结果系统地讨论了由于缺乏融合而导致的层间/轨道空隙，该结果与文献中的实验观察定性一致。