焊接速度对复合板激光对接接头腐蚀性能的影响

Effects of weld speed on corrosion performance of bimetallic sheet butt joint welded by fiber laser

关键词:  双金属复合板  激光焊  元素分布  极化曲线

Key words:  bimetallic plate  laser welding  distribution of element  polarization curve

摘要:

对DSS2205/X65爆炸焊接成形的双金属复合板进行激光穿透对接焊试验，观察了不同的焊接速度下接头的金相显微组织，通过能谱法分析合金元素在焊接接头中的分布，测试了焊接接头复层一侧的动电位极化曲线.结果表明,焊接接头中金相组织沿厚度方向上出现了明显的分层特征；焊缝上部和下部的合金元素发生了相对较小的流动交换；焊接接头复层的极化曲线表明，焊接速度为1.2,1.5,1.8 m/min时接头复层表现出了更好的耐腐蚀性能，而它们的抗点蚀能力随着焊接速度的增大而增大.

Abstract:

The penetration butt welding experiment was carried out on the Dss2205/X65 bimerallic sheet by the fiber laser, The microstructure of weld metal was analyzed with optical microscope. The distribution of the alloying elements element in the welded joints were was analyzed by EDS. The potentiodynamic scanning method was carried out to measurement the anodic polarization curves of welded joints. The experimental results show that the microstrucure of the welded joint exhabits a hierarchical characteristics along thickness direction of welded joints. Polarization curves show that the joints with the welding speed of 1.2 m/min,1.5 m/min, 1.8 m/min showed an better corrosion resistance, and further rmore, With the increase of welding speed, the pitting corrosion resistance of joint is increased.