ABSTRACT

Amongst the many additive manufacturing (AM) techniques, directed energy deposition (DED) is a prominent one, which can also be used for the repair of damaged components. In this paper, we provide an overview on it, with emphasis on the typical microstructures of DED alloys and discuss the processing-microstructure-mechanical property correlations. Comparison is made with those manufactured using the conventional techniques and those obtained with laser beam powder bed fusion (LB-PBF). The characteristic solidification rates and thermal histories in DED result in distinct micro- and meso-structural features and mechanical performance, which are succinctly summarized. The potential of DED for manufacturing graded materials and for component repair is elaborated while highlighting the key-associated challenges and possible solutions. Modelling and simulation studies that facilitate an in-depth understanding of the DED technique are summarized. Finally, some critical issues and research directions that would help develop DED further and extend its application potential are identified.

摘要

在众多增材制造 (AM) 技术中，定向能量沉积 (DED) 是一项突出的技术，它也可用于修复损坏的部件。在本文中，我们对其进行了概述，重点介绍了 DED 合金的典型微观结构，并讨论了加工-微观结构-机械性能的相关性。与使用传统技术制造的产品和使用激光束粉末床熔合 (LB-PBF) 获得的产品进行了比较。DED 中特有的凝固速率和热历史导致了明显的微观和细观结构特征以及机械性能，对此进行了简要总结。阐述了 DED 在制造分级材料和部件修复方面的潜力，同时强调了关键的相关挑战和可能的解决方案。总结了有助于深入了解 DED 技术的建模和仿真研究。最后，确定了一些有助于进一步发展 DED 和扩展其应用潜力的关键问题和研究方向。