激光粉末床熔融技术中铺粉致密度的影响因素研究

Abstract

Laser powder bed fusion (LPBF) technology is one of the most widely used forming technologies in the field of metal additive manufacturing because of its high forming accuracy, low surface roughness, and excellent performance of the formed parts. In this paper, we review the factors influencing powder packing density in LPBF technology, which is a key part of LPBF technology. First, the methods of powder bed quality characterization and evaluation, such as image analysis, Xray insitu monitoring, and sampling method, are summarized. On this basis, the influence of powder particle size, powder morphology, powder preparation method, powder recycling, and powder recoating process parameters on the powder bed packing density is described from powder characteristics and powder recoating process, respectively. Among them, the particle size distribution and morphology of the powder are the key factors affecting the powder packing density, and the wider singlepeak distribution and the bimodal distribution of coarse and fine particles are favorable to improve the powder packing density; the closer the powder morphology is to spherical shape, the better the powder flowability is, which is favorable to improve the powder spreading homogeneity. The powder packing density and spreading homogeneity together will improve the powder bed packing density and the density of formed samples. The change of powder recoating process conditions can influence the powder spreading quality and packing density, among 收稿日期：2022 -08 -10；修回日期：2022 -11 -20；录用日期：2022 -12 -01；网络首发日期：2023 -01 -04 基金项目：国家重点研发计划 (2021YFB3702500)、 国家自然科学基金(51901004) 通信作者： *