激光-电弧复合焊热源相对位置对焊接接头组织与性能影响规律研究

采用20 mm厚EH36钢板堆焊试验研究了激光-电弧复合焊热源相对位置对焊缝宏观形貌、组织、元素烧损和性能的影响规律。结果表明,与电弧引导激光焊接相比,激光引导电弧焊接的焊缝熔深小、熔宽大、熔合比小、焊道对称性差、合金元素烧损率小、显微硬度相对较低;激光引导电弧焊接时,焊缝区晶粒向熔池表面中心生长、晶粒相对粗大,电弧引导激光焊接时,晶粒向着焊缝中心生长、晶粒相对细小,这主要是由于两种热源相对位置不同使得进入焊缝的总能量和熔池流动方向不同造成的。

Study on Influence of Relative Position of Thermal Source of Laser-Arc Hybrid Welding on Composition and Properties of Welded Joint

Laser gas metal arc welding was carried out on 20 mm thick EH36 steel planes to study effects of relative position of thermal source of laser-arc hybrid welding on macroscopic morphology,microstructure,burning rate of alloy and properties of the welded joint.The results show that compared with those of the arc leading welding,for the laser leading welding,the welding seam penetration is shallower,the welding width is bigger,the penetration ratio and the burning rate of alloy are lower,the welded joint becomes less symmetrical and the microhardness of top zone in the welding seam is lower.The grains of welding,large and coarse,are subjected to grow to the surface center of the molten pool by laser leading welding,while the grains of the welding are finer and grow towards the center of the seam by arc leading welding.The reason for such differences is that the position of the heat source is different so that the total energy in welding seam and the direction of molten pool flow are different.