GMAW短路过渡液桥形状动态模型

GNAW(熔化极气体保护焊)短路过渡中的液桥形状变化受诸多因素影响,是一个复杂的动态变化过程.基于能量最小原理,在一定的假设条件下,建立了GMAW短路过渡液桥形状动态变化的模型;结合焊接回路的动态模型,对液桥形状动态变化进行了仿真计算;并在此基础上,进一步进行了模型的试验验证和模型的误差分析.结果表明,建立的GMAW短路过渡液桥形状模型所描述的液桥轮廓动态变化趋势与试验结果比较吻合,实际焊接过程中的液桥形状还受到磁偏吹、焊接运动过程、熔池作用、保护气体流动等的影响,这些影响是造成液桥形状模型误差的主要因素.

Dynamic model of liquid bridge profile in short-circuit transfer of GMAW

Liquid bridge profile in short-circuit transfer of GMAW is affected by many factors, and is a complicated dynamic process.Dynamic liquid bridge profile in GMAW based on principle of minimizing energy has been modeled.Firstly, the energy of a small unit in liquid bridge tends to be minimized under surface tension force, electromagnetic force, and gravity force, so a dynamic liquid bridge profile in GMAW was modeled based on it.Secondly, dynamic behavior of liquid bridge has been simulated and analyzed when dynamic model of GMAWwelding circuit in short-circuit period was associated.Finally, deviations of model were discussed in comparison with the high-speed photography experiment.The research indicates that the dynamic development tendency of liquid bridge profile simulated is consistent with the high-speed photography experimental result, and factors to cause model deviations are arc blow, welding movement, welding pool action and shielded gas lugging.