SLM成形金属薄壁件表面缺陷形成机理研究  

Study on Formation Mechanism of Surface Defects of Metal Thin-wall Parts by SLM

作　　者：左寒松 徐向辉 金文中[1] 柳翊 曹永青 伊浩[2] ZUO Hansong;XU Xianghui;JIN Wenzhong;LIU Yi;CAO Yongqing;YI Hao(Materials Science and Engineering School,Luoyang Institute of Science and Technology,Luoyang 471023,China;State Key Laboratory of Mechanical Transmission,Chongqing 400044,China)

机构地区：[1]洛阳理工学院材料科学与工程学院,河南洛阳471023 [2]重庆大学机械传动国家重点实验室,重庆400044

出　　处：《电焊机》2023年第6期15-22,共8页Electric Welding Machine

基　　金：河南省自然科学基金项目(212300410206);河南省高等学校重点科研项目(21B430012);河南省高等学校重点科技项目(20B430013);洛阳理工学院校内科研项目(2017QZ07);洛阳理工学院高层次人才科研启动项目(2017BZ02,2017BZ04,2017BZ05)。

摘　　要：选区激光熔化技术(SLM)被认为是最具潜力的金属增材制造技术之一。对SLM成形316L不锈钢薄壁件侧壁表面形成机理与优化策略进行了研究。实验结果发现:随着体能量密度的逐渐提升,SLM成形金属薄壁件侧壁粘粉、凹陷(孔隙)等表面缺陷及壁厚精度均呈现分段性变化,即熔池烧结存在固相烧结、稳态传导和非稳定匙孔三种模式。不同体能量密度条件下的熔池热、动力学行为耦合作用改变,使得各种表面缺陷的分布、形貌乃至形成过程均不同。重点分析了叠层褶皱、道内震荡褶皱及飞溅沉积褶皱三类表面褶皱形貌的形成机理。上述研究为提高SLM成形复杂薄壁结构表面质量提供了实验与理论借鉴。Selective laser sintering(SLM)was considered as one of the most potential metal additive manufacturing technologies.The formation and improvement of the side surface quality of 316L thin-walled parts formed by SLM was studied in this paper.The results show that the surface defects including sticking powders,depression(pore),and the wall thickness deviation of SLMed metal thin-walled parts have the similar piecewise change trends with the increase of bulk energy density.It could be inferred that there are three sintering modes of molten pool including solid-state sintering,steady-state conduction and unstable keyhole.Under different bulk energy density,the different coupling effects of the thermal and dynamic behavior of molten pool makes the distribution,morphology and formation mechanism of various surface defects changed.And then the formation mechanism of three kinds of surface ripples was also analyzed innovatively.The above research could provide some experimental and theoretical experience for improving the surface quality of complex thin-walled structures formed by SLM.

关 键 词：选择性激光熔化技术 表面缺陷 熔池行为 金属薄壁件 

分 类 号：TG457[金属学及工艺—焊接]