Modeling and Simulation on Nylon Powder Paving Process in Selective Laser Sintering

Nylon powder is the most mature raw material which is commonly used in Selective Laser Sintering (SLS). The flowability of nylon powder influences the smoothness and density uniformity of the powder bed during the process of powder paving in SLS, which in turn affects the quality of the 3D printing component. The powder paving processes of nylon powder in SLS were simulated using the discrete element method (DEM) to investigate the influence of process parameters and distribution of particle size on the quality of powder bed. Powder paving quality is characterized by build zone dense characteristic and density uniformity. Our numerical results revealed that the density uniformity and dense characteristic of build zone decrease as the roller translational velocity increased between 10 mm/s and 30 mm/s. When the roller translational velocity was greater than 30 mm/s, the density uniformity and dense characteristic of build zone will increase. The results also shown that the dense characteristic of build zone increased as the roller diameter and vibration frequency increasing, the density uniformity of build zone decreased as the standard deviation of particle size distribution increasing.