变层厚打印对选区激光熔化试件成形质量影响研究  

Study on the Effect of Variable Layer Thickness Fabricating on Forming Quality of Specimen by Selective Laser Melting

作　　者：王堃 刘玉德[1] 石文天[1] 韩剑 周裕圣 肖乐欢 Wang Kun;Liu Yude;Shi Wentian;Han Jian;Zhou Yusheng;Xiao Lehuan(School of Artificial Intelligence,Beijing Technology and Business University,Beijing 100048,China)

机构地区：[1]北京工商大学人工智能学院,北京100048

出　　处：《应用激光》2023年第12期34-46,共13页Applied Laser

基　　金：国家自然科学基金(51975006);北京工商大学青年教师科研启动基金;2022年研究生科研能力提升计划项目。

摘　　要：试验以选区激光熔化(SLM)成形TC4固定层厚成形试件的试验研究为基础,提出变层厚打印的成形方法,并设计变层厚叠加方式,探究变层厚试件与固定层厚试件成形质量之间的差异。研究表明,采用200μm→200μm→100μm→100μm→100μm→50μm→50μm→50μm→50μm层厚叠加模式成形的试件致密度高于200μm层厚试件,可达99.13%,成形速率为2.054 mm^(3)/s,优于100μm层厚试件;所得的变层厚试件表面粗糙度为14.2μm,接近50μm层厚试件表面粗糙度。该变层厚试件抗拉强度可达1 047.76 MPa,延伸率可达6.18%,拉伸断口形貌与50μm层厚试件相似。通过显微组织分析可知,该变层厚试件具有较为致密的针状马氏体α′。变层厚成形可为SLM成形提供新的方法,在一定条件下,提高成形质量和成形速率,实现SLM高质量、高速率成形试件。This study explores the selective laser melting(SLM)of TC4 specimens,focusing on the comparison of variable layer thickness fabrication to fixed layer thickness specimens.The forming method of variable layer thickness fabricating was proposed and the superposition method of variable layer thickness was designed to explore the difference between the forming quality of variable layer thickness specimens and fixed layer thickness specimens.The research shows that the density of the specimen formed by 200μm→200μm→100μm→100μm→100μm→50μm→50μm→50μm→50μm forming mode is higher than that of the specimen with 200μm layer thickness,reaching 99.13%,and the building rate is 2.054 mm^(3)/s,which is faster than that of the specimen with 100μm layer thickness.The surface roughness of this forming mode is 14,2μm,which is close to that of the 50μm thickness samples.The tensile strength of the variable thickness specimen can reach 1047.76 MPa,and the elongation can reach 6.18%.The tensile fracture morphology of the variable thickness specimen is similar to that of the 50μm thickness specimen.Microstructure analysis revealed that the variable thickness specimens possess compact acicular martensite a',and their tensile fracture morphology resembles that of the 50μm thickness specimen.The findings demonstrate the potential of variable thickness forming as a novel method in SLM formation,offering improvements in forming quality and rate under certain conditions,thus enabling the realization of high-quality and high-speed SLM-formed specimens.

关 键 词：选区激光熔化 变层厚成形 成形质量 表面粗糙度 力学性能 

分 类 号：TN249[电子电信—物理电子学] TG146.23[一般工业技术—材料科学与工程]