选区激光熔化金属零件后处理技术研究进展

Research Progress on Post-Processing of Metal Parts by Selective Laser Melting

增材制造技术是近年来快速发展的一项先进制造技术,具有成形周期短,材料利用率高,无需模具,节约成本等优点。选区激光熔化(Selective laser melting,SLM)是增材制造工艺的一个重要分支,以激光为热源,通过粉末床熔融的方式实现中小型复杂精密金属结构件的快速成形。除模型设计,零件成形过程本身外,恰当的后处理工艺对于进一步优化组织结构,从而获得符合尺寸要求、表面光洁、力学性能达标的最终产品也十分重要。本文总结了国内外学者针对选区激光熔化零部件后处理方面的研究进展,重点论述了粉末清理与回收、热处理(退火、固溶时效、渗碳/渗氮处理)、热等静压、机械加工(电火花切割、支撑去除、铣削/磨削)、表面处理(喷砂、激光冲击强化、磨粒流)等方面,对改善零件性能,提升产品质量具有积极意义。

Additive manufacturing is a kind of advanced fabricating technology which developed very fast in recent years,it possesses advantages such as short processing procedures,high material utilization rate,no need for mold,cost-saving,and so on.Selective laser melting(SLM)is an important branch of the additive manufacturing process,it is based on the powder bed fusion technique which applies laser as heat source.SLM is capable to form medium and small size complex metal structures with high precision.In addition to structural design and powder bed fusion period,an appropriate post-treatment process is also very important for the final product,which requires fine microstructure,exact size,good surface finish,high mechanical property,and so on.This paper summarizes the research progress of state of the art on the post-treatment of SLM parts,including powder recycling and conditioning,heat treating(annealing,solution aging,carburizing/nitriding treatment),hot isostatic pres-sing,conventional machining(electrical discharge machining,support removal,milling/grinding),surface treatment(sand blasting,laser shot peening,abrasive flow)as well as other aspects.It may be helpful in improving product quality.