脉冲激光SLM工艺参数对钛合金成形质量的影响  

Effect of Process Parameters on Forming Quality of Pulsed Laser SLM Titanium Alloy

作　　者：袁美霞 寇莛彧 刘琪 华明 YUAN Mei-xia;KOU Ting-yu;LIU Qi;HUA Ming(School of Mechanical-electronic and Vehicle Engineering,Beijing University of Civil Engineering and Architecture,Beijing 100044,China)

机构地区：[1]北京建筑大学机电与车辆工程学院,北京100044

出　　处：《表面技术》2023年第11期430-438,共9页Surface Technology

基　　金：国家自然科学基金(51975006);北京建筑大学研究生创新项目(PG2023135)。

摘　　要：目的 针对SLM成形试件表面质量差且边缘凸起严重的现象,研究脉冲激光SLM成形钛合金试件过程中工艺参数对表面质量、边缘凸起行为及致密度的影响规律,优化工艺参数。方法 通过调整曝光时间及点、线间距,制备了15个块状试件,通过激光显微系统来观测表面形貌,分析其表面缺陷,并采集表面粗糙度及平均台阶高度的数据,通过阿基米德排水法测量试件致密度。结果 随着线间距的增大,试件的表面质量及致密性都呈先上升后下降的趋势,而试件边缘平面和中间平面的平均高度差则是先增大后减小;随着曝光条件的增强,试件的表面质量和致密性都呈下降的趋势,而试件边缘平面和中间平面的平均高度差则在一定程度上减小。当线间距、曝光时间、点间距分别为0.1 mm、60μs、30μm时,试件表面粗糙度最小,为2.563μm,致密度最大为97.03%;当线间距、曝光时间、点间距分别为0.15 mm、80μs、40μm时,试件边缘平面和中间平面的平均高度差最小,为69.865μm。结论 在低曝光条件下,试件各个位置的表面粗糙度较为均匀,适当调整线间距有利于获得表面质量和致密性良好、表面缺陷较少的试件,并且在一定程度上SLM成形钛合金的表面粗糙度和致密性存在相关性。高曝光条件虽然会降低试件的表面质量,但在一定程度上可以减少试件边缘的凸起现象。At present,the SLM process forming test piece still has the disadvantages of poor surface quality,obvious edge bulge,and internal porosity,so the test piece can not be directly applied to the scenarios with high accuracy requirements.In this test,15 groups of test pieces were formed by adjusting the line spacing,exposure time and point spacing of SLM forming process.The Kearns VK-X250K shape measurement laser microscope system was used to obtain the data of the surface roughness,surface morphology,and the average height difference between the edge plane and the middle plane of the test piece.At the same time, the density of the test piece was tested by Archimedes drainage method. The effect law of line spacing, point spacing and exposure time on the surface quality and density of the test piece was found, and the reason for the edge bulge of the test piece was elucidated. By quantifying the phenomenon of the edge bulge of the test piece with the optical microscope system, the effect law of the process parameters on the edge bulge of the test piece was found. It was found that with the increase of the line spacing, the surface quality and compactness of the test piece firstly increased and then decreased. The average height difference between the edge plane and the middle plane of the test piece increased firstly and then decreased. When the exposure conditions were properly increased, the surface quality and compactness of the test piece tended to decline, while the average height difference between the edge plane and the middle plane of the test piece decreased to a certain extent. When the line spacing, exposure time and point spacing were 0.1 mm, 60 μs and 30 μm respectively, the minimum surface roughness of the test piece was 2.563 μm, and the maximum density was 97.03%. When the line spacing, exposure time and point spacing were 0.15 mm, 80 μs and 40 μm respectively, the average height difference between the edge plane and the middle plane of the test piece was at least 69.865 μm. The difference of sur

关 键 词：工艺参数 SLM 钛合金 表面质量 致密度 边缘凸起 

分 类 号：TG665[金属学及工艺—金属切削加工及机床]