冷却环境对DH36钢摩擦叠焊接头连接质量的影响

Effect of Cooling Environment on the Joint Connection Quality of DH36 Steel Friction Stitch Welding

为了确定摩擦叠焊方法在不同海域的应用条件,采用天津大学自主研制的摩擦叠焊设备,分别在水温2~3℃和水温18~20℃条件下,对DH36钢进行了水下摩擦叠焊工艺试验。试验结果表明,水温高（18~20℃）时的摩擦叠焊接头质量明显优于水温低（2~3℃）时的接头质量,接头拐角处的缺陷长度较小;水温低（2~3℃）时,焊缝中心组织主要为板条马氏体,局部区域有少量板条贝氏体组织,水温高（18~20℃）时,焊缝中心组织主要为板条贝氏体。

In order to determine the application conditions of friction stitch welding method in different sea area, adopting the friction stitch welding equipment, developed by Tianjin University, to conduct underwater friction stir welding process test for DH36 steel, respectively at the temperature of 2~3 ℃ and 18~20 ℃. The test results indicated that when water temperature is high（18~20 ℃）, the friction stitch welding joint quality is obviously better than that of friction stitch welding when the water temperature is low（2~3 ℃）, the defects length of the joint corner is smaller; when water temperature is low（2~3 ℃）, the weld microstructure is mainly composed of martensite, a small amount of lath bainite in local area, when the temperature is high（18~20 ℃）, weld center organization is mainly lath bainite.