Abstract This paper proposes a double-wire pulsed gas metal arc welding (GMAW) process with a median current waveform based on traditional double-wire pulsed GMAW. A high-speed digital camera and digital oscilloscope were used to simultaneously record the metal transfer process as well as the voltage and current waveforms under different median currents. The median pulse was modeled as an exponential function and a mathematical model of the droplet diameter was established. Further, variation of the output current during the welding process and the influence of pulse parameters on the metal transfer process were accurately described. The results show that the median current has a significant impact on the metal transfer process. When the median current increases, the metal transfer period gradually decreases and the desired one drop per pulse (ODPP) mode, with a moderate droplet size and no droplet collision, is almost achieved within an appropriate median current range. As the median current gradually increases, the droplet diameter also increases but then begins to decrease as the median current further increases and gets closer to the peak current. The droplet offset distance first decreases considerably, then begins to increase, and droplet collision occurs as the median current continues to increase, resulting in an unstable transfer process. Initially, the transfer time decreases and then increases, followed by a subsequent decrease as the median current continues to increase.

中文翻译：

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具有中值波形的铝合金双线脉冲GMAW的金属转移

摘要 本文在传统双丝脉冲GMAW的基础上，提出了一种具有中值电流波形的双丝脉冲气体保护金属电弧焊(GMAW)工艺。使用高速数码相机和数字示波器同时记录金属转移过程以及不同中值电流下的电压和电流波形。将中值脉冲建模为指数函数并建立液滴直径的数学模型。此外，准确描述了焊接过程中输出电流的变化以及脉冲参数对金属转移过程的影响。结果表明，中值电流对金属转移过程有显着影响。当中值电流增加时，金属转移周期逐渐减少，并且几乎在适当的中值电流范围内实现了所需的每脉冲一滴 (ODPP) 模式，具有适中的液滴尺寸和无液滴碰撞。随着中值电流逐渐增加，液滴直径也增加，但随后随着中值电流进一步增加并接近峰值电流而开始减小。液滴偏移距离先显着减小，然后开始增加，随着中值电流的不断增加，液滴发生碰撞，导致转移过程不稳定。最初，传输时间减少然后增加，随后随着中值电流继续增加而减少。随着中值电流逐渐增加，液滴直径也增加，但随后随着中值电流进一步增加并接近峰值电流而开始减小。液滴偏移距离先显着减小，然后开始增加，随着中值电流的不断增加，液滴发生碰撞，导致转移过程不稳定。最初，传输时间减少然后增加，随后随着中值电流继续增加而减少。随着中值电流逐渐增加，液滴直径也增加，但随后随着中值电流进一步增加并接近峰值电流而开始减小。液滴偏移距离先显着减小，然后开始增加，随着中值电流的不断增加，液滴发生碰撞，导致转移过程不稳定。最初，传输时间减少然后增加，随后随着中值电流继续增加而减少。随着中值电流的不断增加，液滴碰撞发生，导致转移过程不稳定。最初，传输时间减少然后增加，随后随着中值电流继续增加而减少。随着中值电流的不断增加，液滴碰撞发生，导致转移过程不稳定。最初，传输时间减少然后增加，随后随着中值电流继续增加而减少。