Effect of Particle Size Distribution on the Properties of Sand Mold by Three Dimensional Printing

In this study, three dimensional structures are fabricated by a self-developed three dimensional printing machine with eight different particle size distribution scrubbed silica sand. In order to evaluate particle size distribution effect on the properties of sand mold, the physical and mechanism properties of printed specimens, including weight, gas evolution, air permeability, tensile strength and compressive strength, were measured. The mechanism of effect was analyzed and studied. The results show that the printed specimens from the 80-140 mesh sand powder have the best comprehensive properties. Both wider and narrower particle size distribution adversely affects the properties of printed specimens.

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Effect of Particle Size Distribution on Particle Dynamics and Blade Erosion in Axial Flow Turbines

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2906284 ◽

1991 ◽

Vol 113 (4) ◽

pp. 607-615 ◽

Cited By ~ 30

Author(s):

W. Tabakoff ◽

A. Hamed ◽

M. Metwally

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Gas Turbines ◽

Three Dimensional ◽

Axial Flow ◽

Coal Ash ◽

Particle Dynamics ◽

Material Erosion ◽

Effect Of Particle Size

This work presents the results of an investigation conducted to study the effect of coal ash particle size distribution on the particle dynamics, and the resulting blade erosion in axial flow gas turbines. The particle dynamics and their blade impacts are determined from a three-dimensional trajectory analysis within the turbine blade passages. The particle rebound conditions and the blade material erosion characteristics are simulated using empirical equations, derived from experimental measurements. For the typical ash particle size distribution considered in this investigation, the results demonstrate that the size distribution has a significant influence on the blade erosion intensity and pattern.

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Three-Dimensional Modeling of Green Sand and Squeeze Molding Simulation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.925.473 ◽

2018 ◽

Vol 925 ◽

pp. 473-480 ◽

Cited By ~ 1

Author(s):

Yuuka Ito ◽

Yasuhiro Maeda

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Three Dimensional ◽

Hard Core ◽

Sand Mold ◽

Particle Model ◽

Three Dimensional Model ◽

Green Sand ◽

Squeeze Pressure

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.

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