为了促进船用高强钢结构激光焊接技术发展，利用光纤激光对8 mm 厚的10CrSiNiCu钢板进行了填丝对接焊接。分析了焊接接头的微观组织形貌与硬度、拉伸、弯曲和冲击等力学性能，研究了焊接热输入对接头组织与性能的影响。结果表明，10CrSiNiCu 钢激光焊焊缝区组织主要为马氏体+铁素体+贝氏体；热影响区粗晶区组织主要为块状铁素体+粒状贝氏体+马氏体。焊接接头硬度分布不均匀，焊缝区硬度最高，热影响区次之。当焊接线能量从5.00 kJ/cm 降至3.64 kJ/cm 时焊缝区硬度从346 HV 增加至396 HV。接头拉伸试样均断裂在母材。3 倍板厚压头作用下焊接试样可正向弯曲约113°，比母材降低近60°。熔合线和焊缝区的低温(-40 ℃)冲击功随着焊接热输入的增加而先增加后减小，在E=4.20 kJ/cm 时熔合线和焊缝区的冲击功最高，分别达到95 J和101 J，冲击试样断口均呈韧性断裂特征。

To promote the mechanical properties of marine high strength steels joints, fiber laser butt welding on 8 mm thick 10CrSiNiCu steel is performed by using filler wire. The microstructures, hardness, tensile strength, bending property and impact energy (at sub-zero temperature) of the welded joints are analyzed. Also, the effects of welding heat input on microstructures, hardness and fracture behavior of the welded joints are also studied. The results show that the microstructure of the weldment mainly consists of martensite + ferrite + bainite, and its hardness is the highest among the welded joint zones. When heat input decreases from 5.00 kJ/cm to 3.64 kJ/cm, the average hardness of weldment increases from 346 HV to 396 HV. Tensile specimens are all broken in base metal. A bending angle of 113° can be reached at room temperature, which is 60° lower than base metal. At the heat input of E=4.20 kJ/cm, the impact energy at fusion line and weld seam reaches its highest value, 95 J and 101 J, respectively.