能量密度对选区激光熔化AlSi12合金成形质量的影响  

Effect of energy density on forming quality of selective laser melted AlSi12 alloy

作　　者：杨政 吴敬 高杰 卢云[1] Yang Zheng;Wu Jing;Gao Jie;Lu Yun(School of Materials Science and Engineering,Anhui University of Technology,Maanshan Anhui 243000,China)

机构地区：[1]安徽工业大学材料科学与工程学院,安徽马鞍山243000

出　　处：《金属热处理》2025年第4期200-207,共8页Heat Treatment of Metals

摘　　要：为明确激光能量密度作为选择性激光熔化(SLM)工艺优化依据的可靠性,本文通过正交试验设计,考察体能量密度(不同激光功率、扫描速度和扫描间距的工艺组合)对SLM成形铝合金组织和性能的影响。利用SLM成形技术制备AlSi12合金,通过光学显微镜、扫描电镜和室温拉伸试验对合金的致密度、熔池尺寸、微观组织和力学性能等进行表征和研究。结果表明,在相同体能量密度下,随着激光功率的提升,熔池加深,熔池边缘热影响区的等轴晶比例下降,细晶区组织逐渐粗化;随着扫描速度的提升,熔池变宽,细晶区等轴枝晶比例增大,粗晶区组织细化,热影响区细小Si颗粒逐渐增多。体能量密度不能作为成形件质量判断的唯一影响因素。激光功率对致密度、抗拉强度和屈服强度的影响最大,而扫描速度对伸长率影响最大。合金试样在激光功率为300 W、扫描速度为1200 mm/s和扫描间距为60μm时力学性能最优,抗拉强度为447.1 MPa,屈服强度为433.7 MPa,伸长率为7.6%。In order to clarify the reliability of laser energy density as a basis for selective laser melting(SLM)process optimization,the effect of volume energy density(process combinations of different laser powers,scanning speeds and scanning spacing)on the microstructure and properties of SLM-formed alloy by means of an orthogonal experimental design was investigated.The AlSi12 alloy was fabricated by SLM forming technology,and the densities,melt pool boundary,microstructure and mechanical properties of the alloy were characterized and investigated by optical microscope,scanning electron microscope and room temperature tensile tests.The results show that under the same volume energy density,with the increase of the laser power,the melt pool deepens,the proportion of equiaxed grains in the heat-affected zone at the edge of the melt pool decreases,and the microstructure of the fine grain zone gradually coarsens;while with the increase of the scanning speed,the melt pool broadens,the proportion of equiaxed dendrites in the fine grain zone increases,the microstructure of the coarse grain zone refines,and the fine Si particles in the heat-affected zone gradually increase.The volume energy density cannot be used as the only influencing factor for the judgement of quality of the shaped parts.The laser power has the greatest influence on densification,tensile strength and yield strength,while the scanning speed has the greatest influence on elongation.The mechanical properties of the specimens are optimal at the laser power of 300 W,scanning speed of 1200 mm/s and scanning spacing of 60μm,with the tensile strength of 447.1 MPa,yield strength of 433.7 MPa and elongation of 7.6%.

关 键 词：激光选区熔化 AlSi12合金 能量密度 正交试验 力学性能 

分 类 号：TG146.21[一般工业技术—材料科学与工程]