2003 年 75 巻 2 号 p. 102-107
A three-dimensional simulation model for green sand molding was developed using Distinct Element Method (DEM) in the present study. The characteristics of bonded sand such as sand shape and particle distribution were expressed by the Hard-Core/Soft-Shell model. Contact force and gravitational force moved individual particles. The present model was applied to squeeze molding. Laboratory experiments were carried out to test the validity of the model. Furthermore, two- and three-dimensional simulation using uniformed elements were carried out to compare the compaction behavior. Results of the experiment and simulation clarified the relationship between the void fraction and squeeze pressure during molding. The effects of particle size distribution on sand compaction behavior were also clarified. Mold properties obtained by simulation using non-uniform elements more or less agreed with those by experiments.