双钨极氩弧焊焊缝成形的数值模拟

Numerical simulation on weld formation of twin-electrode GTAW welding

采用数值模拟方法对双钨极氩弧焊的焊缝成形规律进行研究。考虑到两个电弧的相互吸引作用导致电弧偏转,仿真时采用倾斜热源模型。对比分析了单、双钨极氩弧焊的焊缝成形特点,研究了双钨极氩弧焊焊接过程中钨极间距、电流大小和匹配形式对熔池形状的影响。结果表明,相对于单钨极氩弧焊,双钨极氩弧焊的熔宽窄,熔深略小;随着钨极间距的增加,熔宽增加,熔深减小;随着电流的增大,熔深和熔宽都有一定程度的增加;两钨极上焊接电流的不同匹配形式会对焊缝成形产生影响。

The weld formation of twin-electrode tungsten inert gas (T-TIG) welding was studied with numerical simulation. With a view to the arc deflection from the mutual attraction between the two arcs, inclined heat source model was adopted. The weld formation features of T-TIG and traditional TIG were comparatively analyzed. The effects of electrode distance, the current value and the matching of currents on the shape of melting pool were studied. The results show that compared with single-electrode tungsten inert gas, the weld width of T-TIG is narrower, and the weld depth is little smaller; with the increasing of electrode distance, the weld width increases, the weld depth decreases; With the increase of currents, the weld depth and width both increase; the current matching forms between electrodes also have certain influences on the weld formation.