Abstract Electron Beam Selective Melting (EBSM) is an advanced additive manufacturing technique used in many vital industrial fields. However, the lack of process monitoring and quality control is largely restricting the industrial application. The optical-based monitoring methods are hindered by the complex working conditions, such as intensive radiation, elevated temperature, and severe evaporation. Electronic imaging is an alternative monitoring technique which has been introduced into EBSM process. However, the correlation between the electronic signal and topographic features has not been identified. In this study, a dual-detector electronic imaging system was presented for in-situ monitoring of EBSM process. The preliminary experiment shows a linear correlation between the electronic current and surface height gradient, suggesting a sensitive response of the electronic imaging system to surface height variation. In-situ experiment indicates that the electronic imaging system is capable of visualizing the deposited surfaces with plentiful contrasts. Signal fusion between the dual detectors was able to separate the mixed contrasts for identifying various defects, such as pores and fluctuations. The correlation between signal and topography indicates a good potential for in-situ surface reconstruction and in-process quality control during EBSM process.

中文翻译：

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电子束选择性熔化的双探测器电子监测

摘要 电子束选择性熔化（EBSM）是一种先进的增材制造技术，用于许多重要的工业领域。然而，缺乏过程监控和质量控制在很大程度上限制了工业应用。基于光学的监测方法受到复杂的工作条件的阻碍，例如强辐射、高温和严重蒸发。电子成像是一种替代的监测技术，已被引入 EBSM 过程。然而，尚未确定电子信号与地形特征之间的相关性。在这项研究中，提出了一种双探测器电子成像系统，用于 EBSM 过程的原位监测。初步实验表明电子电流和表面高度梯度之间存在线性相关性，表明电子成像系统对表面高度变化的敏感反应。原位实验表明，电子成像系统能够以丰富的对比度可视化沉积表面。双检测器之间的信号融合能够分离混合对比以识别各种缺陷，例如孔隙和波动。信号和地形之间的相关性表明在 EBSM 过程中原位表面重建和过程质量控制的良好潜力。双检测器之间的信号融合能够分离混合对比以识别各种缺陷，例如孔隙和波动。信号和地形之间的相关性表明在 EBSM 过程中原位表面重建和过程质量控制的良好潜力。双检测器之间的信号融合能够分离混合对比以识别各种缺陷，例如孔隙和波动。信号和地形之间的相关性表明在 EBSM 过程中原位表面重建和过程质量控制的良好潜力。