Abstract The three-dimensional (3-D) simulation of powder particle entering melt pool during laser solid forming (LSF) was carried out in our quest to establish a general representative model of this phenomenon. The effect of the gas-liquid interface on the motion state of the powder was analyzed, and the accuracy and universality of the model were verified using a high-speed photographic experimental approach. Further, the simulation process of the Ti-6Al-4V powder particle entering the high-temperature Ti-6Al-4V melt pool was carried out. The effects of the gas-liquid interface of the melt pool on the motion state of the powder particle and the disturbing of the powder particle on the melt pool were studied. It was found that the running speed of the particle experienced a rapid decrease and then a slower decrease in the process of entering the pool. Also, the particle serves as a transport medium of gases and carries the gases into the pool, which could form pores in the deposited layer. When the particles enter the melt pool at varied speeds, the ratio of the instantaneous speed of the particle entering the pool to the initial incident speed differs, which increases with increasing initial speed.

中文翻译：

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激光固体成形过程中粉末颗粒与熔池气液界面的相互作用

摘要 我们对激光固体成形 (LSF) 过程中粉末颗粒进入熔池的三维 (3-D) 模拟进行了研究，以建立这种现象的一般代表性模型。分析了气液界面对粉体运动状态的影响，采用高速照相实验方法验证了模型的准确性和通用性。进一步对Ti-6Al-4V粉末颗粒进入高温Ti-6Al-4V熔池进行了模拟过程。研究了熔池气液界面对粉粒运动状态的影响以及粉粒对熔池的扰动。发现粒子的运行速度在进入水池的过程中经历了快速下降然后缓慢下降。此外，颗粒充当气体的传输介质并将气体带入池中，这可能会在沉积层中形成孔隙。当粒子以不同的速度进入熔池时，粒子进入熔池的瞬时速度与初始入射速度的比值不同，随着初始速度的增加而增大。