Influence of impact medium particle size on mechanical deposition layer formation process based on discrete element method

Abstract

Based on the discrete element method, this study has simulated the movement of materials in the plated barrel using EDEM software to investigate the effect of the impact medium with different particle sizes on the mechanical deposition plating. The simulation analyzed the interaction between five impact mediums with different particle sizes (2, 3, 4, 5, and 6 mm) and the base body while determining the particle size ratio of the impact medium. The rationality of the particle size ratio was verified by the simulation analysis of the interreaction of two groups of mixed particle size impact medium and the base body. The samples of mechanically deposited zinc coating were prepared. The average thickness, relative density, and average deviation of the coating were measured. The results show that When the particle size is 2 and 3 mm, the effective collision frequency of the materials is higher. When it is 3, 4, and 5 mm, the kinetic energy of collision between materials fluctuates evenly. When it is 4 and 5 mm, the collision contact force of the materials changes regularly. Consequently, the obtained particle size ratio (second group) is 2 mm 23%; 3 mm 23%; 4 mm 23%; 5 mm 27%; and 6 mm 4%. Compared with mixed impact media with 20% of each of the five particle sizes (first group), in the second group of assorted particle size simulation test, the collision frequency between materials is high. The contact force changes more regularly between materials. The average thickness, relative density, and average deviation of the mechanically deposited galvanized layer are consistent with the simulation results of the two groups of mixed particle sizes. The average thickness and relative density of the galvanized layer in the second group are higher, the average deviation is smaller, and the compactness and uniformity are the best.