Shuji Ohsaki, Takeru Yano, Hideya Nakamura, Satoru Watano
Department of Chemical Engineering, Osaka Metropolitan University
Purpose.
Powder compression has been utilized in various industries, including pharmaceuticals, foods, metals, and batteries. Although powder properties affect the compact structure, these effects remain unclear. In this study, we used the discrete element method to investigate the effects of particle cohesiveness and plasticity on the compression of bimodal powders.
Methods.
The DEM is a numerical method for powder motion that considers the motion of each element based on Newton’s second law. The Edinburgh elastoplastic adhesion model, which considers particle cohesiveness and plastic deformation, was applied as the contact model. The particle plasticity λp was varied from 0 to 0.7. The macroscopic and microscopic properties of the powder compression were investigated.
Results.
In contrast to that for the elastic model, the void fraction at Vf = 0.5 was smaller than that at Vf = 0.3 for the high plastic condition (λp = 0.7). In addition, as the number of fine particles increased, the largest contact type changed in the order of coarse–coarse, coarse–fine, and fine–fine. The plasticity of the particles enhanced the effects of fine particle addition.
Conclusions.
This study demonstrated that the plasticity of the particles affected both the macroscopic and microscopic powder properties. It is important to determine the optimal addition ratio of fine particles based on the plastic deformability of the material [1].
Reference.
[1] Takeru Yano, Shuji Ohsaki, Hideya Nakamura, Satoru Watano, “Compression properties of bimodal powders with different plasticities in the elastoplastic powder compression process: A numerical analysis”, Advanced Powder Technology, 34, 1042445 (2023)