| Abstrakt: |
The green sand mold with good mold properties are useful to obtain the sound cast iron castings. For example, the green sand mold with high density and uniform for compacting characteristics would be required. Molding simulation is indispensable to make a good sand mold. In recent years, the package software was released from software vendors of foundry CAE, and the demand for molding simulation is increasing. Fundamental algorithms of the green sand particulate model and the three-dimensional Discrete Element Method (DEM) were proposed. They take into consideration of the particle size distribution and the cohesion of green sand particles.In this study, the squeeze molding simulation is carried out and we execute the re-development of this method under the current computer environment. They are tried to simulate the dynamic behavior during molding and to predict the mold properties after squeeze molding. The characteristics of green sand with cohesion are reflected in the particle model called Hard-Core/Soft-Shell. The compacting behavior of squeeze molding is traced numerically, and the visualization by a three-dimensional model and comparison of dynamics molding are carried out. From the simulation with several kinds of particle distribution, it becomes clear the relationship between the void fraction and the squeeze pressure during molding. The effect of particle size distribution on sand compacting behavior is also clarified. Furthermore, the three-dimensional display of green sand with particle size distribution is very effective in the post-processing. |
