Journal of Materials Engineering and Performance

, Volume 21, Issue 9, pp 1893–1903 | Cite as

Optimization of Gating System Design for Die Casting of Thin Magnesium Alloy-Based Multi-Cavity LCD Housings

Article

Abstract

High-pressure die casting is the preferred process for manufacturing Mg-alloy components used for numerous applications. High-pressure die casting is suitable for mass production and has the advantage of also being suitable for accurately fashioning objects of complicated shapes. One disadvantage of high-speed die casting is the occurrence of defects such as shrinkage or air entrainment. Gating system design must be very effective in actual manufacturing facilities to avoid the occurrence of such defects. The objective of this study is to present a methodology for obtaining optimal designs of 4-cavity thin electronic component housings. The fluid behavior and amount of air entrainment caused by the overflows and air vent designs were analyzed using a computer fluid dynamics (CFD) simulator. The effectiveness of the proposed system was demonstrated through CFD simulations and experiments using an actual manufacturing process. Also, the effect of vacuum systems on the porosity and mechanical properties of the castings was studied. The volume of porosity in the casting was found to be significantly reduced using vacuum assistance during die casting. As a result, the tensile strength and the elongation of the die casting products are improved.

Keywords

AZ91D die casting mechanical properties microstructure numerical simulation 

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Copyright information

© ASM International 2012

Authors and Affiliations

  1. 1.Division of Material Science and EngineeringInha UniversityIncheonRepublic of Korea

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