在CaF₂-SiO₂-TiO₂-CaO系药粉中分别添加质量比为1：1，2：1，3：1的镍、铬元素，以2205不锈钢带为外皮材料制备了自保护药芯焊丝；利用该焊丝对2205双相不锈钢进行了电弧焊，研究了镍铬质量比对焊缝显微组织和力学性能的影响。结果表明：随着镍铬质量比的增大，焊缝中的奥氏体相增多、铁素体相减少，且奥氏体相的尺寸增大；未添加镍、铬元素时，焊缝的强度最高、塑性最差，冲击功最小，为72 J；随着镍铬质量比的增大，焊缝强度下降，塑性和冲击功增大；当镍铬质量比为3：1时，焊缝冲击功最高，为150 J。

The Ni and Cr elements were added in CaF₂-SiO₂-TiO₂-CaO base powder with Ni to Cr mass ratio of 1:1, 2:1, 3:1, respectively, then the self-shield flux cored wires were prepared with 2205 stainless steel strip as wrapping material. Using the prepared welding wires, 2205 duplex stainless steel was arc welded, and the effects of Ni to Cr mass ratio on the microstructure and mechanical properties of the weld seam were studied. The results show that with the increase of Ni to Cr ratio, the austenite phase content in the weld seam increases, the ferrite phase content decreases and the size of austenite phase increases. Without the addition of Ni and Cr elements, the strength of the weld seam was the largest while the plasticity was the lowest, and the impact energy was the smallest, which was 72 J. With the increase of Ni to Cr ratio, the strength of the weld seam decreases while the plasticity and impact energy increase. When the mass ratio of Ni to Cr was 3:1, the impact energy of the weld seam had the highest value of 150 J.