Numerical Simulation Of Three Dimensional Particle Suppression With Heterogeneous Non-Equal Diameter Random Arrangement

In the process of compaction and densification of heterogeneous non-equal diameter random powder particles,the deformation characteristics and laws of the particles in the cavity are difficult to recognize.The traditional method is to repeatedly measure the compactness of the compact through a test method,which not only consumes time,but also increases production costs.This paper uses JAVA programming language to construct random non-equal-diameter powder particles(taking Cu-W powder particles as an example)in the actual state of complex natural accumulation in engineering practice,and simulates the MSC.MARC from a microscopic point of view through finite element analysis The state of the powder particles in the compression molding process,in order to discover the characteristics of the powder particles in the compression deformation,so as to improve the production process,reduce production time,and save production costs.This article first solves the problem of how to construct a geometric model of the accumulation of powder particles in a natural state,and then analyzes the displacement,strain,and node flow trajectories of the powder particles during the compaction process,and analyzes the densification process(friction coefficient,Temperature)and the effects of interchangeable materials on density.Finally,the simulation results were verified by experiments.The research results and innovations obtained in this paper are as follows:(1)Based on JAVA programming language,the initial loose packing state of Cu-W three-dimensional powder particles randomly accumulated in the cavity is realized,and the initial loose packing relative density is 41.602%.(2)The finite element software MSC.MARC is used to suppress heterogeneous non-equal diameter random powder particles.The simulation results show that: in the initial stage of pressing,the powder particles in the mold cavity flow from top to bottom as a whole,and the deformation near the punch is the largest.When the compression reaches a steady state,there are still gaps between the particles due to the elastic aftereffect.(3)The strain process of a single particle was studied,and the results showed that the contact deformation between particles and the mold wall is inconsistent.The Cu particles located in the initial stage of compaction tended to move downward and the rotation trend was not obvious.The Cu particles located in the mid-pressing zone have significant downward movement and rotation trends.During the entire pressing process,most of the W particles showed obvious movement and rotation trends,and only a few movement characteristics were not obvious.This difference is mainly because Cu has a lower yield strength than W,and the material will affect the density of the product.(4)The effects of temperature,friction coefficient and powder material on densification were studied.The results show that when the temperature increases from200℃ to 1000℃,the relative density increases from 90.04% to 92.19%,which is a 2.15%difference.When the friction coefficient increases to 0.4,the final density of the compact is 90.670%.When the hard powder particles are doped to a large size,the final compactness of the compact is only 85.480%.In actual production,a proper particle size ratio,friction and temperature can increase the density of the product.