Effects of Casting Conditions on the Mold Filling Characteristics of Mg Alloy in the EPC Process

With consideration of the viscosity of semi-solid aluminum alloy slurry and the mold filling characteristics in die casting, the die-casting mould for semi-solid aluminum alloy has been designed and manufactured on the basis of the standard samples. The process of mold filling and solidification of semi-solid aluminum alloy in die casting was simulated by using ProCAST software. With combination of simulation results with die casting experimental data, the results indicate that the influence of heating system of the mould and cross section of ingate for the mould on flowing of semi-solid aluminum alloy in mould cavity is important in this work.

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Functions of Step Gating System in the Lost Foam Casting Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.591-593.940 ◽

2012 ◽

Vol 591-593 ◽

pp. 940-944 ◽

Cited By ~ 1

Author(s):

Hong Zhou ◽

Li Heng Luo

Keyword(s):

Mass Flux ◽

Flux Ratio ◽

Casting Process ◽

Mold Filling ◽

Lost Foam Casting ◽

Gating System ◽

Bottom Side ◽

Total Mass Flux ◽

Filling Characteristics ◽

Lost Foam

In order to explore whether the step gating system played a role in lost foam casting (LFC) process, this paper simulated the mold filling process of a step gating system with an auxiliary sprue and three side ingates by using the gravity LFC model of the code FLOW-3D, and analyzed its mold filling characteristics in LFC. It is found the mass flux ratio through the bottom-side ingate exceed 82% the total mass flux, much more than through the others. And it is also found the metal temperature of the middle region in the height direction is lower than the upper region or bottom region. The results show that the step gating system is not able to achieve its main roles in LFC. Our results can be used to design gating system in LFC.

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Effects of Casting Conditions on the Mold Filling Characteristics of Mg Alloy in the EPC Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.2753 ◽

2005 ◽

Vol 475-479 ◽

pp. 2753-2756

Author(s):

Kyeong Hwan Choe ◽

Gue Serb Cho ◽

Kyong Whoan Lee ◽

Akira Ikenaga

Keyword(s):

Polymethyl Methacrylate ◽

Mold Filling ◽

Expanded Polystyrene ◽

Back Pressure ◽

Gas Pressure ◽

Pouring Temperature ◽

Reduced Pressure ◽

The Difference ◽

Filling Characteristics ◽

Expendable Pattern

Mold filling characteristics in the Mg Expendable Pattern Casting(EPC) process were investigated in terms of casting conditions such as reduced pressure, pouring temperature and casting modulus including foam materials. With increasing pouring temperature up to 775oC the filling velocity increased. However, the filling velocity decreased at temperatures above 775oC. This is likely due to the increase of back pressure. Concerning the effect of reduced pressure on filling velocity, it increased sharply at lower reduced pressure while became stable at higher reduced pressure. In thick pattern, high reduced pressure would be needed to obtain high filling velocity. In expanded polystyrene(EPS) patterns, mold filling was found to be faster in the thick pattern than thin pattern at temperatures below 750oC. This propensity was observed to be reverse at pouring temperatures above 750oC. In polymethyl methacrylate(PMMA) patterns, the filling velocity almost leveled off without showing a dependence of pouring temperature. This result is attributed to the difference in gas pressure between EPS and PMMA patterns during the EPC process.

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Mold-Filling Characteristics of AZ91 Magnesium Alloy in the Low-Pressure Expendable Pattern Casting Process

Journal of Materials Engineering and Performance ◽

10.1361/10599490522211 ◽

2005 ◽

Vol 14 (1) ◽

pp. 132-135 ◽

Cited By ~ 2

Author(s):

H.B. Wu ◽

Z.T. Fan ◽

N.Y. Huang ◽

X.P. Dong ◽

X.F. Tian

Keyword(s):

Magnesium Alloy ◽

Casting Process ◽

Low Pressure ◽

Mold Filling ◽

Az91 Magnesium Alloy ◽

Az91 Magnesium ◽

Filling Characteristics ◽

Expendable Pattern

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Lattice imaging of precipitates in Al-Zn-Mg alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143651 ◽

1986 ◽

Vol 44 ◽

pp. 412-413

Author(s):

C. K. Wu

Keyword(s):

Grain Boundaries ◽

Homogeneous Nucleation ◽

Alloy System ◽

Mg Alloy ◽

List Type ◽

Lattice Structures ◽

Type Number ◽

Orientation Relationships ◽

Lattice Imaging ◽

The Matrix

The precipitation phenomenon in Al-Zn-Mg alloy is quite interesting and complicated and can be described in the following categories:(i) heterogeneous nucleation at grain boundaries;(ii) precipitate-free-zones (PFZ) adjacent to the grain boundaries;(iii) homogeneous nucleation of snherical G.P. zones, n' and n phases inside the grains. The spherical G.P. zones are coherent with the matrix, whereas the n' and n phases are incoherent. It is noticed that n' and n phases exhibit plate-like morpholoay with several orientation relationship with the matrix. The high resolution lattice imaging techninue of TEM is then applied to study precipitates in this alloy system. It reveals the characteristics of lattice structures of each phase and the orientation relationships with the matrix.

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