磁控带极电渣堆焊熔池行为的研究

An Investigation into Molten Pool Behavior of Electro-slag Bead Welding with Strip under Magnetic Field

本文针对带极电渣堆焊熔池体积大的特点,利用焊前在试板的纵、横向镶嵌铜条,焊后检测铜质点在堆敷金属中分布的方法,结合熔池温度的测定,研究了带极电渣堆焊的熔池行为。结果表明,熔池表面和底部的温度都低于电弧焊,这是造成低稀释率的根本原因;熔池内熔融金属流动速度的分布是由熔池温度分布决定的;熔池在外磁场力的作用下,当磁控电流增大或磁棒与带极距离增大时,焊道宽度增大,表面平整,咬边被消除。

In connection with the feature of greater molten pool volume for electro-slag bead welding with strip under magnetic field, an investigation into molten pool behavior of above mentioned welding is conducted in this paper by using inlaying eopper bar in parent metal before welding, measuring the distribution of copper particles in the deposit after welding, and along with measuring the temperature of the molten pool. The result shows that the temperatures of molten pool surface and bottom are lower than those ones in arc welding. This is main cause of formation of low dilution rate. The velocity distribution of molten metal in the pool is determined by temperature distribution in molten pool. Under the action of external magnetic field, weld bead width increases and its surface is smoothed with the increase of magnetically controlled current or with the increase of the distance between magnetic bar and the strip, and the cutdown is eliminated.