摘要
在AlSi10Mg合金雾化粉末中添加2%纳米TiB2颗粒和1%亚微米SiC颗粒(均为质量分数),通过低能球磨制备(TiB2+SiC)/AlSi10Mg复合粉末,并采用激光选区熔化(SLM)技术制备(TiB2+SiC)/AlSi10Mg复合材料。采用X射线衍射(XRD)、背散射电子衍射(EBSD)、扫描电镜(SEM)等手段对比研究(TiB2+SiC)/AlSi10Mg复合材料和AlSi10Mg合金的显微组织,并测定材料的拉伸性能。结果表明,(TiB2+SiC)/AlSi10Mg复合粉末的激光反射率低于AlSi10Mg合金粉末的激光反射率(分别为31%和46%),可在较低激光功率(240 W)下进行激光选区熔化成形制备性能优良的(TiB2+SiC)/AlSi10Mg复合材料。TiB2和SiC陶瓷增强颗粒均匀分布,无明显团聚,少量TiB2聚集长大至微米级。通过用(TiB2+SiC)颗粒混杂增强,AlSi10Mg合金的平均晶粒尺寸从7.88μm减小至2.48μm,晶粒组织由粗大柱状晶转变为细小等轴晶及少量短棒状晶,抗拉强度由453.1 MPa提高至509.8 MPa,伸长率从7.2%提高至10.6%。
The(TiB2+SiC)/AlSi10Mg composite powders,with 2%nano-TiB2 particles and 1%submicron-SiC particles were prepared by low-energy ball milling and used for selective laser melting(SLM)process.The microstructures and mechanical properties of aluminum matrix composites(AMCs)reinforced with hybrid TiB2 and SiC and AlSi10Mg alloy were studied by XRD,EBSD and SEM.The results show that the laser reflectivity of the composite powders reduces from 46%to 31%compared to that of AlSi10Mg alloy powders.AMCs reinforced with TiB2 and SiC,with excellent properties,were successfully prepared by SLM at a low laser power of 240 W.Nano-TiB2 particles and submicron-SiC particles are uniformly distributed inside the grains,but a few nano-TiB2 particle sagglomerate and growup tomicron-scale.With the addition of nano-TiB2 particles and submicron-SiC particles,the coarse columnar grains are transformed into equiaxed grains and the average grain size decreases from 7.88μm to 2.48μm.The tensile strength,ductility increase to 509.8 MPa,10.6%,respectively.
作者
沈君剑
刘允中
欧阳盛
洪旭潮
刘小辉
SHEN Junjian;LIU Yunzhong;OUYANG Sheng;HONG Xuchao;LIU Xiaohui(National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials,South China University of Technology,Guangzhou 510640,China)
出处
《粉末冶金材料科学与工程》
EI
北大核心
2020年第3期251-259,共9页
Materials Science and Engineering of Powder Metallurgy
基金
广东省重点领域研发计划资助项目(2019B090907001)
广东省科技计划资助项目(2014B010129002,2016B090913001)。
关键词
激光选区熔化
颗粒混杂增强铝基复合材料
显微组织
力学性能
SLM
hybrid particles reinforced aluminum matrix composites
microstructures
mechanical properties