Gas metal arc (GMA) welding requires improved process stability, higher quality and efficiency, and quantitative control of the heat input and deposition. These requirements can be achieved by appropriately controlling the metal transfer phenomenon. However, this control method has primarily been applied to short-circuit transfer, and very few examples of its application to free-flight transfer exist. Therefore, the effect of wire feed control on free-flight transfer remains unclear. In this study, the influence of wire feed control on the free-flight transfer phenomenon in the GMA welding process using an aluminum wire electrode was investigated through experimental observations, and free-flight transfer control was attempted.

It was observed the free-flight transfer phenomenon, particularly globular transfer, under low-current conditions with controlled wire feeding under various feed conditions, using wire feed–retract speeds and cycles as parameters. The observation results revealed two patterns with different timings of droplet detachment under long- and short-period conditions. Furthermore, the observation of the droplet detachment motions revealed that the inertia caused by the acceleration or deceleration of the feed speed acts on the droplet. Moreover, the difference between the two transfer patterns is primarily caused by the inertia acting on the droplet before and after switching the wire feed–retract direction and the size of the droplet at that time. Based on this, free-flight transfer can be stabilized by reconfiguring the feed conditions.

熔化极气体保护焊 (GMA) 需要提高工艺稳定性、更高的质量和效率以及热输入和熔敷的定量控制。这些要求可以通过适当控制金属转移现象来实现。但这种控制方法主要应用于短路转移，应用于自由飞行转移的例子很少。因此，送丝控制对自由飞行传输的影响仍不清楚。本研究通过实验观察研究了送丝控制对铝丝电极GMA焊接过程中自由飞行过渡现象的影响，并尝试了自由飞行过渡控制。

在低电流条件下，使用送丝-缩回速度和周期作为参数，在各种送丝条件下控制送丝，观察到自由飞行转移现象，特别是球状转移。观察结果揭示了在长周期和短周期条件下液滴脱离时间不同的两种模式。此外，对液滴脱离运动的观察表明，由进给速度的加速或减速引起的惯性作用于液滴。此外，两种转移模式之间的差异主要是由切换送丝/缩回方向之前和之后作用于熔滴的惯性以及当时熔滴的尺寸引起的。在此基础上，可以通过重新配置进给条件来稳定自由飞行转移。