60mm厚16Mn特厚板焊接接头组织及力学性能研究

Study on Microstruture and Mechanical Properties of Welding Joints for 60mm Thickness 16Mn Super Thick Plate

利用埋弧自动焊法对60mm厚16Mn特厚板进行焊接,采用ZEISS光学显微镜、LEICA显微硬度计及扫描电镜观察分析了焊接接头各区域及母材的组织、硬度,以及拉伸断口的形貌。结果表明:在本文的焊接实验条件下,焊接接头各区域的组织明显不同,上部区域粗大,下部区域细小;硬度值在过热区达到最高;焊接接头的拉伸断裂为韧性断裂,其抗拉强度均小于母材的抗拉强度。

Using the method of automatic submerged-arc welding, 60 mm thickness 16Mn super thick plate was welded. The microstructure, microhardness, tensile strength and fracture appearance of the welded joints and base metal were observed and analyzed by the means of ZEISS optical microscope, LEICA microhardness tester and SEM. The results show that the microstucture of the welding joints are apparently different, which is coarse at the upper part and fine at the lower part. The maximum micro-hardness is found in the welded overheated zone, meanwhile the welded seam fracture is toughness fracture, and the tensile strength of the welded joints is smaller than that of the base metal under the welding experiment condition.