激光选区熔化用AlSi10Mg粉末显微组织与性能

摘要

采用超音速气体雾化制备AlSi10Mg粉末,粉末经分级后通过激光选区熔化制成试块.利用金相显微镜、扫描电子显微镜、X射线衍射仪研究粉末和试块的微观组织、组成相及演变情况,通过拉伸实验测试试块的室温拉伸性能.结果表明,AlSi10Mg粉末粒径分布符合激光选区熔化工艺要求,粉末呈球形或类球形.粉末组织细小均匀,主要由α(Al)基体和(α+Si)共晶组成.试块熔池形貌清晰可见,组织均匀、致密,其致密度达到99.5％;该组织中仅存在α(Al)和极少量Si相,几乎所有合金元素均固溶于Al基体中.经室温拉伸性能测试,试块的抗拉强度达到了442 MPa.%The AlSi10Mg powder was prepared by supersonic gas atomization. After classified,the powder was fabricated into block by selective laser melting (SLM). The microstructure,phase,and evolutions of powder and block were investigated by optical micro-scope,scanning electron microscope and X-Ray Diffraction. The tensile properties of SLM block were tested by tensile experiments at room temperature. The results show that the size distribution of AlSi10Mg powder after classified can meet the requirements of SLM technology. The powder always is spherical and spherical-like. Meanwhile,the microstructure of powders is fine and uniform,which contain α(Al)matrix and (α+Si)eutectic. In addition,the melt pool boundaries of SLM block are legible. The microstructure is al-so uniform and densified,the relative density approaches to 99. 5％. On the other hand,onlyα(Al)and few Silicon phase are detec-ted in this condition,due to the most alloying elements are dissolved in α(Al)matrix. At room temperature,the ultimate tensile strength of SLM block reaches up to 442 MPa.