增材制造GH3625粉末三维成像与空心粉分析

Three-dimensional imaging and hollow powder analysis of GH3625 powder for additive manufacturing

摘要:

以增材制造GH3625金属粉末为研究对象,采用扫描电镜观察了粉末样品的二维微观结构,通过显微CT表征了粉末样品的三维结构,定量分析了粉末的粒度、体积、球度等几何特征参数。通过三维分割成功提取了空心粉内部所有孔隙,分别以体积孔隙率、空心粉概率、球度等多种参数表征了3D打印的粉末质量。最后研究了空心粉内部孔隙的直径对粉末颗粒球度的影响。实验结果表明,显微CT是一种表征增材制造金属粉末质量的理想工具,CT实验共探测到20576个GH3625粉末颗粒,粉末的平均粒度为28.16μm,其中空心粉颗粒数量为1440个,内部孔隙数量1515个,少数粉末颗粒存在多个孔隙,发现空心粉颗粒的球度随着空心粉内部孔隙直径增大而降低。

Abstract:

The research object were additive manufacturing GH3625 metal powders,the two-dimensional microstructure of the powders were observed by scanning electron microscopy(SEM), the three-dimensional structure of the powders were characterized by micro-CT,and the geometric parameters such as particle size, volume and sphericity of the powders were quantitatively analyzed. All the pores inside the hollow powders were successfully extracted by three-dimensional(3D) segmentation, and the 3D printed powder quality was characterized by volume porosity, probability of hollow powder, sphericity and other parameters.Finally, the influence of the pore diameter in the hollow powder on the sphericity of powders were investigated. The experimental results show that micro-CT is an ideal tool to characterize the quality of metal powders of additive manufacturing, a total of 20576 GH3625 powder particles were detected by CT, the average particle diameter of the powder is 28.16 μm, the number of hollow powder particles is 1440,the number of internal pores is 1515, and a few powder particles have multiple pores,it is found that the sphericity of the hollow powder particles decreases with the increase of the internal pore diameter of the hollow powders.