The present work aimed at evaluating the effect of O₂ content in argon-based shielding gases over the arc cathodic emission behavior (which can lead to arc wandering) in wire + arc additive manufacturing (WAAM) of thin aluminum walls and its consequences over layer formation. The effect of O₂ content on arc wandering was assessed by analyzing cathodic spot behavior through high-speed videography during Gas metal arc (GMA-AM) depositions. Superficial and geometric aspects were analyzed, as well as the sputtering zone width on the wall sides. Through a proposed model, a parallel effect of wire-introduced oxides was weighted to explain arc wandering, searching for oxides in the wall sides (deviating from its action only on the pool). The main finding was that no influence of O₂ from the shielding gas was observed on arc wandering, consequently on layer formation, when its content was up to 200 ppm. When an O₂ content of 20,000 ppm was employed, oxide searching by the arc in the wall sides was no longer perceived due to enough oxide availability from the shielding gas. However, this favorable condition to layer formation entailed excessive layer oxidation. From the cathodic emission point of view, it can be said that high-purity shielding gases or special mixtures with small additions of O₂ (up to 200 ppm) provide no significant advantages for WAAM of aluminum thin walls, at least for the hereby tested alloy and parameters.

本工作旨在评估薄铝壁的线+电弧增材制造（WAAM）中基于氩气的保护气体中O ₂含量对电弧阴极发射行为（可能导致电弧漂移）的影响，以及其对涂层的影响编队。O ₂的作用  通过在气体金属电弧（GMA-AM）沉积过程中通过高速摄像来分析阴极斑点行为，评估了电弧漂移的含量。分析了表面和几何方面以及壁侧的溅射区宽度。通过提出的模型，加权了导线引入的氧化物的平行效应，以解释电弧游荡，在壁侧搜索氧化物（由于其仅作用于水池）。主要发现是，当其含量高达200 ppm时，没有观察到来自保护气体的O ₂对电弧漂移的影响，因此对层的形成没有影响 。当O ₂含量为20,000时 使用ppm，由于保护气体中有足够的氧化物可利用，因此无法再感觉到电弧在壁侧搜寻氧化物。但是，这种有利的层形成条件导致过度的层氧化。从阴极发射的角度来看，可以说，高纯度的保护气体或少量添加O ₂（最高200 ppm）的特殊混合物对铝薄壁的WAAM并没有明显的优势，至少对于经过测试的合金和参数。