论文部分内容阅读
提出了一种采用外特性自适应控制实现短路CO2焊电磁力与表面张力自均衡过渡方法。基于提出的缩颈过程液桥表面形态变化规律的简化模型,文中对不同液桥形态下表面张力性质进行了分析,考虑到熔池波动等因素对液桥形态的影响,单纯依靠表面张力过渡必然存在由于液桥不能及时爆断而引发的稳定性问题。在研究了电磁收缩力和液桥半径及短路电流的关系、液桥电阻和液桥半径的关系之后,设计了本文的方案。试验结果证明,此种方法不仅可以有效提高短路液桥缩颈过程中电流的衰减速度,减小短路液桥爆断前集聚的能量并达到减小飞溅的效果,同时又实现了电磁力与表面张力的自动均衡,确保了熔滴的平稳过渡和液桥的及时断开,有效改善了焊接过程的稳定性。
A self-adaptive control of external characteristics to achieve a short-circuit CO2 welding electromagnetic force and surface tension self-balanced transition method. Based on the proposed simplified model for the change of liquid bridge surface morphology during the necking process, the surface tension under different liquid bridge configurations was analyzed. Taking into account the influence of the fluctuation of the molten pool on the liquid bridge morphology, the inevitable reliance on the surface tension transition There is a stability problem caused by the liquid bridge not being able to burst in time. After studying the relationship between the electromagnetic contractility and liquid bridge radius and short-circuit current, the relationship between liquid-bridge resistance and liquid-bridge radius, the scheme of this paper has been designed. The experimental results show that this method not only can effectively improve the current decay speed in the process of short circuit liquid bridge necking, but also reduce the energy accumulated before the short circuit liquid bridge ruptures and achieve the effect of reducing the splashing. At the same time, the electromagnetic force and the surface Tension automatically balanced to ensure a smooth transition of the droplet and liquid bridge timely disconnect, effectively improve the stability of the welding process.