喷嘴形状对铝合金复合焊接头成形质量的影响

Influence of nozzle shape on the quality of aluminum joints product by laser-arc hybrid welding

为了研究气体喷嘴形状对焊接成形质量的影响,采用了建立不同形状喷嘴的外流场数值模型的方法,进行了数值仿真和实验验证。在相同工艺参量下,采用YAG激光-MIG电弧复合热源,对10mm厚的5083铝合金板进行了平板堆焊试验。结果表明,多排圆管喷嘴的焊接过程最稳定,焊缝熔深和熔宽最大,分别为9.41mm和4.45mm,但其气孔率却最高达7.34%;单个方管的保护效果最好,但其焊接过程稳定性、熔深和熔宽均介于多排圆管与单个圆管喷嘴之间;而单个圆管除了保护效果介于多排圆管与单个方管之间外,其过程稳定性最差,焊缝形貌特征值最小;保护气体喷嘴为方形时,保护效果最佳。该结果验证了数值模型计算所得到的各种喷嘴有效保护范围和气流挺度。

In order to research the effect of different nozzle shapes on the quality of weld forming joint,numerical simulation of flow field of different shape nozzles were established by FLUENT software.The testing of bead-on-plate welding to 5083 aluminum alloy plate with 10mm thickness was carried out under the same processing parameters by using Nd∶YAG-MIG hybrid welding.After experimental verification,the results show that,the welding stability of multi-row round nozzle is the best,and weld penetration and weld width are the largest,9.41mm and 4.45mm respectively,but the porosity is up to 7.34%.The protective effect of single side square nozzle is the best,but its welding stability,weld penetration and weld width are between multi row round nozzle and single side round nozzle.Protection effect of single side round nozzle is between multi row round nozzle and single side square nozzle,and then,welding stability and characteristic value of welding appearance have the worst results.Protection effect of square nozzle is the best.The research illustrates numerical simulation of protection effective range and airflow stiffness of different nozzle shapes.