标题： 硅纳米颗粒在激光诱导正向转移（LIFT）打印过程中结晶的分子动力学（MD）模拟 显示英文标题

标题： Molecular Dynamics (MD) simulation of silicon nanoparticle crystallization during laser-induced forward transfer (LIFT) printing

摘要： 激光诱导正向转移（LIFT）打印是一种实现功能材料（包括金属和半导体）微/纳米尺度增材制造的通用技术。 然而，LIFT打印过程中的结晶现象尚未得到充分理解。 在本工作中，我们尝试全面了解LIFT打印过程中硅的结晶行为。 具体而言，使用分子动力学（MD）模拟研究了空气传输过程中硅纳米颗粒的尺寸效应对其熔化和结晶的影响。 我们发现，随着纳米颗粒尺寸的减小，即使冷却速率较低，结晶也变得罕见。 还分析了不同颗粒的成核位置，几乎总是从亚表面位置（低于5 {\AA }）开始。 在凝固过程中监测原子结构的演变，以为硅的LIFT打印提供指导。 我们的模拟结果表明，纳米限制可能导致单晶结构的形成，这可能有助于单晶增材制造。 显示英文摘要

摘要： Laser-induced forward transfer (LIFT) printing is a versatile technique to realize micro/nano-scale additive manufacturing of functional materials, including metals, and semiconductors. However, the crystallization phenomena during LIFT printing have not been well understood. In this work, we attempt to gain a comprehensive understanding of silicon crystallization during LIFT printing. Specifically, molecular dynamics (MD) simulation is used to investigate the size effect on the melting and crystallization of Si nanoparticles during transportation in air. We found with the decrease in nanoparticle size, crystallization becomes rare, even with a low cooling rate. The nucleation location of different particles is also analyzed and almost always starts at a sub-surface location (below 5 {\AA}). The atomic structure evolution during solidification is also monitored to provide guidance for LIFT printing of Si. Our simulation results indicate that nano-confinement can lead to single-crystal structure formation, which may shed light on single-crystal additive manufacturing.