电弧作用下熔透型TIG熔池液面行为的数值模拟

在正面熔化半径RZ和板厚h一定的条件下,基于对有电弧作用的熔透型TIG焊接熔池三维液面行为的分析,获得了不同背面熔化半径RB的熔池三维形状模型,利用有限元分析软件surface evolver进行数值模拟,研究了电弧对熔透型TIG焊接熔池液面的影响.结果表明,电弧的作用与否对熔池下液面的大小和形状无显著的影响;在背面熔化尺寸较小时(RB≤2.5 mm附近),电弧对上液面特征量有较大作用;电弧的作用从整体上是使熔池上液面压低.在从脉冲基值过渡到脉冲峰值期间,电弧电压(或弧光光强)增加的部分是由电流增加和熔池上液面被压低两部分引起的.

Numerical simulation on effect of TIG welding arc on liquid surface of full-penetrated molten pool

When top fusion zone radius and plate thickness are constant,the three-dimensional shape model at different back fusion zone radius was obtained by analyzing three-dimensional liquid surface of TIG(tungsten inert-gas) welding full-penetrated molten pool with the arc.The effect of the arc on liquid surface of TIG welding full-penetrated molten pool was investigated through numerical simulation with finite element analysis software(Surface Evolver).The results show that the size and shape of the back liquid surface of molten pool aren't influenced remarkably by the arc.However,when the back fusion zone radius is small(about less than or equal to 2.5 mm),the effect of the arc on the characteristic parameters of the top liquid surface is obvious,and the top liquid surface is depressed by the arc.From the pulse base value to the pulse peak value,the arc voltage or the arc light intensity is increasing,which is due to not only the current increasing but also top liquid surface of the molten pool being depressed.