Fiber laser and gas metal arc hybrid welding of 440-MPa-grade high-strength marine steel was carried out at different welding speeds. The influence of welding speed on the microstructure and mechanical properties of weld metal was investigated. The weld-metal microstructure mainly consisted of pre-eutectoid ferrite, side-plate ferrite, acicular ferrite and lath bainite at a low welding speed. With the increase in welding speed, acicular ferrite and lath bainite were the dominant weld-metal microstructures. All samples failed at the base metal during tensile tests, which indicates that there is no soft zone in the hybrid welds. The welding speed had a significant effect on the impact toughness of the weld metal. The impact absorbed energy of the weld metal increased from 35 to 105 J with the increase in welding speed from 0.8 to 2.0 m/min. Large amounts of acicular ferrite and lath bainite were formed in the weld metal at a high welding speed, which resulted in an excellent impact toughness.

在不同的焊接速度下进行了440 MPa级高强度船用钢的光纤激光和气体金属电弧混合焊接。研究了焊接速度对焊接金属组织和力学性能的影响。焊缝金属组织主要由低速焊接时的共析铁素体，侧板铁素体，针状铁素体和板条贝氏体组成。随着焊接速度的提高，针状铁素体和板条贝氏体成为主要的焊接金属组织。在拉伸试验中，所有样品都未通过母材，这表明混合焊缝中没有软区。焊接速度对焊接金属的冲击韧性有重要影响。焊接金属的冲击吸收能从35 J增加到105 J，焊接速度从0.8 m / min增加到2.0 m / min。