本文采用HG-2型高功率CW CO_2激光器对有色金属Ni进行了熔凝处理。实验材料是纯度为99.9％的电解Ni。实验结果表明纯Ni的激光熔凝组织特征明显有别于Fe及其合金的激光熔凝组织、纯镍经激光熔凝处理后,其熔化区内存在大量的各种缺陷。这些缺陷包括激光熔化区与其基体的严重分层;熔凝区内存在大量球形气泡和显微空隙;同时,熔化金属被严重氧化,经x衍射分析判明这些氧化产物主要是NiO和Ni_3N。本文深入探讨了形成这些缺陷的原因。 In this paper, HG-2 high-power CW CO_2 laser was used to treat non-ferrous metal Ni. The experimental material is electrolytic Ni of 99.9% purity. The experimental results show that the laser fusion microstructure of pure Ni is obviously different from that of Fe and its alloys. Pure nickel possesses many defects in the melt zone after laser fusion. These defects include severe delamination of the laser melting zone and its matrix; a large number of spherical bubbles and micro-voids exist in the melting zone; meanwhile, the molten metal is severely oxidized. The XRD analysis shows that these oxidation products are mainly NiO and Ni_3N. This article explores in depth the causes of these pitfalls.