作为金属粉末激光快速成型技术中送粉系统的关键部件之一, 送粉喷嘴的送粉效率直接影响金属粉末激光快速成型的效率和精度。国内外对此领域都进行了深入研究, 并研制出多种新型送粉喷嘴, 其中同轴送粉喷嘴能有效提高金属粉末的熔覆效果和利用率。详细介绍了同轴送粉喷嘴的送粉原理及国内外研究现状, 分析及总结了影响光粉耦合效果和粉末利用率的主要因素, 并提出了改进方法。针对激光聚焦、粉末偏聚和反弹、冷却效果不佳等缺陷提出了改进措施, 并对同轴送粉喷嘴的应用前景进行了展望。

As one of key components of powder feeding system in the technology of laser rapid prototyping for metal powder, the powder feeding efficiency of powder feeding nozzles influences directly the laser rapid prototyping efficiency and accuracy of metal powder. The in-depth studies at home and abroad are performed in this field and a variety of new powder feeding nozzles are developed in which the coaxial powder feeding nozzle can effectively improve the metal powder cladding effect and utilization. The feeding principle and the research status at home and abroad of coaxial powder feeding nozzles are introduced, the main factors influencing powder utilization and laser-powder coupling performance are analyzed and summarized, and the improvement methods are proposed. Improvement approaches for laser focusing, powder segregation and bounce, and poor cooling efficiency are proposed, and the applications of coaxial powder feeding nozzles are prospected.