ABSTRACT This work deals with Directed Energy Deposition (DED) that is a process in which the material is delivered directly into the melt pool. Several kinds of nozzle have been developed and used in this process. However, the position of the nozzle, mainly for the lateral one, plays a crucial role in the geometry and porosity content of the melt pool. Therefore, to investigate the correlation between the lateral nozzle position and the geometry of the melt pool, three different sets of single tracks of Ti–6Al–4V were deposited at different nozzle positions. It was found that helpful information regarding the selection of the optimal position of the lateral nozzle can be obtained from the melt pool features. It can be noticed that by increasing the distance between the nozzle position and substrate, the powder capture decreases and accordingly results in a high depth of fusion zone and also keyhole defect formation.

中文翻译：

---

在定向能量沉积过程中，喷嘴位置如何影响熔池的几何形状

摘要 这项工作涉及定向能量沉积 (DED)，这是一种将材料直接输送到熔池中的过程。在这个过程中已经开发和使用了几种喷嘴。然而，喷嘴的位置，主要是侧向喷嘴，对熔池的几何形状和孔隙率起着至关重要的作用。因此，为了研究横向喷嘴位置与熔池几何形状之间的相关性，在不同的喷嘴位置沉积了三组不同的 Ti-6Al-4V 单轨。发现可以从熔池特征中获得关于侧向喷嘴最佳位置选择的有用信息。可以注意到，通过增加喷嘴位置和基板之间的距离，