选区激光熔化WC-12Co单层成形工艺与形貌组织分析  

Optimization and Morphology Analysis of Single-Layer Forming Process Parameters of Selective Laser Melting WC-12Co

作　　者：贾娜[1] 张纯朴[1] 王春昕 余本军 刘九庆[1] Jia Na;Zhang Chunpu;Wang Chunxin;Yu Benjun;Liu Jiuqing(Northeast Forestry University,Harbin 150040,Heilongjiang,China)

机构地区：[1]东北林业大学机电工程学院,黑龙江哈尔滨150040

出　　处：《应用激光》2024年第12期1-11,共11页Applied Laser

基　　金：国家重点研发计划(2022YFD2202105)。

摘　　要：利用选区激光熔化(SLM)技术对钴碳化钨合金粉末进行不同工艺参数组合下的单道单层扫描实验。使用光学显微镜分析不同工艺参数下的单道宽度变化规律,主要从搭接率、能量密度2个方面分析讨论了单层表面形貌形成机制,通过超景深三维显微系统(super depth of field 3D microscope system)分析了激光功率、扫描速度、扫描间距3个工艺参数对粗糙度的影响。通过扫描电子显微镜(SEM)分析了单层截面形貌,使用扫描电子显微镜附带的能量色散X-射线光谱仪(EDS)分析了单道的元素分布。结果显示,激光功率和扫描速度主要通过线能量密度影响单道宽度,线能量密度越大则单道宽度越宽。在单层形成过程中,搭接率是影响单层形貌的关键因素,搭接率越高则单层整体的表面粗糙度越小,不同的工艺参数都是通过影响单层的搭接率从而对单层形貌产生影响。在同一扫描间距下,激光功率和扫描速度通过影响单道宽度进而影响单层的搭接率,而当激光功率和扫描速度一定时,扫描间距则直接影响单层的搭接率。此外,单层形成过程中,其截面内部会产生W元素聚集现象,而这种现象是影响单层表面质量的重要因素之一。当激光功率为420 W,扫描速度为500 mm·s^(-1),激光扫描间距为125μm,铺粉层厚为40μm时,单层的表面质量最好,其粗糙度为6.05μm。Selective Laser Melting(SLM)technology was employed to conduct single-pass monolayer scanning experiments on cobalt tungsten carbide alloy powder under,exploring various combinations of process parameters.Analysis of the singlepass width variation under different parameters,particularly focusing on lap rate and energy density,elucidated the formation mechanism of monolayer surface morphology.The effects of laser power,scanning speed,and scanning pitch on roughness were investigated using the Super Depth of Field 3D Microscope System.Additionally,the cross-sectional morphology was examined via Scanning Electron Microscope(SEM),with elemental distribution analyzed using SEM's attached energy spectrometer.Results revealed that laser power and scanning speed predominantly influenced monolayer width through line energy density,with higher line energy density resulting in wider monolayer width.In the process of monolayer formation,the lap rate emerged as a pivotal factor in monolayer morphology,with higher lap rates correlating with lower overall surface roughness.Various process parameters affect the lap rate of the monolayer,thereby impacting its morphology.Laser power and scanning speed influence single-channel width,consequently affecting the lap rate within the same scanning spacing.Additionally,a certain combination of laser power and scanning speed directly affects the lap rate of the monolayer when the laser scanning spacing is fixed.Agglomeration of tungsten(W)elements within the monolayer cross-section was observed,potentially impacting surface quality.Optimal surface quality,with a roughness of 6.O5μm,was achieved at a laser power of 420W,scanning speed of 500mm-s^(-1),scanning spacing of 125μm,and powder layer thickness of 40μm.

关 键 词：选区激光熔化 碳化钨粉末 粗糙度 搭接率 

分 类 号：TG135.5[一般工业技术—材料科学与工程]