[2] [2] ZHOU J H, ZHANG Y W, CHEN J K. Numerical simulation of random packing of spherical particles for powder-based additive manufacturing［J］. Journal of Manufacturing Science and Engineering, 2009, 131(3): 1.

[3] [3] KRNER C, ATTAR E, HEINL P. Mesoscopic simulation of selective beam melting processes［J］. Journal of Materials Processing Technology, 2011, 211(6): 978-987.

[4] [4] CHEN H, WEI Q S, WEN S F, et al. Flow behavior of powder particles in layering process of selective laser melting: Numerical modeling and experimental verification based on discrete element method［J］. International Journal of Machine Tools and Manufacture, 2017, 123: 146-159.

[5] [5] TANG C, TAN J L, WONG C H. A numerical investigation on the physical mechanisms of single track defects in selective laser melting［J］. International Journal of Heat and Mass Transfer, 2018, 126: 957-968.

[8] [8] PANWISAWAS C, QIU C L, ANDERSON M J, et al. Mesoscale modelling of selective laser melting: Thermal fluid dynamics and microstructural evolution［J］. Computational Materials Science, 2017, 126: 479-490.