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应用具有自由表面的流体稳定性理论，解释了高速焊接时驼峰焊道的产生机理，并通过对熔池形成过程的实时图像采集对该理论进行了验证。理论分析和试 验结果均表明，采用自由过渡 的熔滴过渡形式进行焊接，工件始终处于焊接电弧的加热下， 在高速焊接时，熔池不能及时冷 却，熔 池明显拉长，由扰动引起的振动波长大，当熔池的拉长达到一定程度时，会发 生液体金属的失稳和颈缩 的现象，造成驼峰焊道。在此基础上提出，可以采用短路过渡代替高电压下的自由过渡，利用短路过渡时电弧周期性的熄灭可以减小对熔池的加热量，防止熔池过长而失稳。试验结果表明，采用短路过渡焊接可以有效地防止驼峰焊道的产生，提高焊接速度。
The fluid stability theory with free surface is applied to explain the mechanism of the production of the hump weld bead during high speed welding. The theory is validated by real-time image acquisition of the weld pool formation process. The theoretical analysis and experimental results show that the free-transition molten droplet transition forms the workpiece and the workpiece is always heated by the welding arc. At high-speed welding, the molten pool can not be cooled in time and the molten pool obviously lengthens. The vibration caused by the disturbance Wavelength, when the molten pool reaches a certain degree of elongation, the liquid metal instability and necking will occur, resulting in hump bead. On the basis of this, it is suggested that the short-circuit transition can be used instead of the free transition under high voltage, the periodic extinguishment of the arc can be used to shorten the heating of the molten pool and prevent the molten pool from being too long and unstable. The test results show that the use of short-circuit transition welding can effectively prevent the emergence of hump bead, improve the welding speed.