对3 mm厚的C18000铜合金板分别进行了激光焊接和激光填丝焊接研究，重点分析了焊缝的组织、成分和力学性能。结果表明，直接采用激光焊接时，焊缝出现了晶粒长大的现象，显微硬度为90 HV，强度仅为313 MPa；采用ERNiCu-7焊丝进行激光填丝焊时，焊缝内Ni的质量分数自上而下从31%降至10%，焊缝组织为单相固溶体，显微硬度提高到130~180 HV，强度提高到391 MPa，性能优于直接激光焊接的。

The research on laser welding and laser welding with filler wires of 3-mm thick C18000 copper alloy plates is conducted. The microstructures, compositions and mechanical property of welds are analyzed emphatically. The results show that, in the case of direct laser welding, the growth of weld grains appears, the weld microhardness is 90 HV, and the weld strength is only 313 MPa. While in the case of laser welding with ERNiCu-7 filler wires, the mass fraction of Ni from top to bottom of the welds drops from 31% to 10%, the weld structure is single-phase solid solution, the weld microhardness increases to 130-180 HV, and the weld strength increases to 391 MPa. These performances are superior to those for the direct laser welding.