试验采用TIG填丝焊和CO2激光焊两种工艺方法对08Al钢进行对接焊, 通过电化学腐蚀试验研究两种焊接接头的母材、热影响区及焊缝区的耐蚀性能。结果表明, CO2激光焊接头热影响区的耐蚀性优于母材, 母材的耐蚀性优于TIG填丝焊热影响区, TIG填丝焊热影响区的耐蚀性优于CO2激光焊焊缝区, TIG填丝焊焊缝区的耐蚀能力在所有测试区域中最差, 腐蚀表面点蚀坑最多。分析认为, 焊缝区和热影响区受热输入量的影响不同, 导致焊后晶粒尺寸、组织形态及分布不同是耐蚀性存在差异的主要原因, 焊缝合金元素含量和焊后残余应力对金属耐蚀能力的影响并不明显。

The 08Al steel weld joints were obtained through the way of TIG welding with wire and CO2 laser welding respectively. The corrosion resistance of the base material(BM), heat affect zone(HAZ)and fusion zone(FZ)were tested by electrochemical experiment. The results indicate that the heat affect zone corrosion resistance of CO2 laser welding is superior to base material and the base material corrosion resistance is better than the heat affect zone of TIG welded joints with wire. The fusion zone corrosion resistance of CO2 laser welding is inferior to the heat affect zone of TIG welding with wire. The fusion zone corrosion resistance of TIG welding with wire is worst in all of the test areas and its surface has many corrosion pits. The main reason is the different effect of heat input lead to the different grain size, microstructure and its distribution. In addition, the content of alloying elements in fusion zone and the inequable residual stress have little impacts on corrosion resistance.