中文摘要：

为研究水深对湿法焊接质量的影响,采用相同的焊接工艺参数在高压舱内模拟不同水深湿法FCAW焊接双相不锈钢S32101。利用Matlab提取焊缝横截面轮廓并计算主要成形尺寸（熔深、熔宽和余高）;采用光学显微镜和Image-Pro Plus软件研究不同水深焊缝结合区、焊缝中心区和热影响区的显微组织及铁素体含量。结果表明：不同水深焊缝横截面轮廓差异很大,尤其是80 m水深焊缝横截面轮廓曲线极其不光滑;随着水深的增加,熔宽几乎无变化,熔深先减小后增大,余高先增大后减小;焊缝结合区、焊缝中心区和热影响区组织随水深增加均有细化倾向;热影响区奥氏体相含量随水深增加而减小,但焊缝中心区奥氏体含量随水深增加反而增大。

英文摘要：

To study the influence of water depth on the quality of wet welding, we use the same welding parameters to simulate different water depths while welding duplex stainless steel S32101 by wet flux-cored arc welding（FCAW） in a hyperbaric chamber. We extract the cross section of each weld,and we use MATLAB to calculate the main shaping dimensions （ penetration, weld width, and excess weld metal） . We inspect the microstructures of the binding areas, cntral areas, and heat-affected zones using an optical microscope, and we apply the Image-Pro Plus software to determine the ferrite content of each weld. The results show considerably different cross-sectional features at different water depths. In particular, the weld cross-section at a water depth of 80 m is extremely coarse. As the water depth is increased, the weld width remains roughly the same. The penetration decreases ini-tially with water and then increases, whereas the excess weld metal increases initially and then decreases. The mi-crostructure morjDhologies of the binding areas, center areas, and heat-affected zones become more refined with in-creasing water depth ; the austenite content decreases in the heat-affected zones, but becomes progressively higher in the center area of the weld.