Principal Investigator

Assoc. Prof. Dr. Nguyen Hong Hai
Hanoi University of Science and Technology (HUST), Vietnam

ASEAN Co-Investigator

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Japanese Co-Investigator

Prof. Dr. Keiichi ISHIHARA
Kyoto University

Awarded year

2014

Program

Collaborative Research Program with Industry (CRI)

Field

Materials Engineering

Abstract

For automobile and engine spare parts, which are important for “localization” of automobile industry in Vietnam and which are mostly made of light metals, such as aluminum and magnesium, the diecasting is the most popuparly applied method. But there are two main disvantages of diecasting: 1) formation of denderitic microstructure with many defects interdendritic and intergranular; 2) formation of pores due to turbulent character of melt flow fulfilling the mold. These disvantages can be overcome by combining diecasting with rheocasting, to generate so-called rheo-diecasting process. In this research, the rheocasting process was carried out by implementing at the same time two methodes: near-liquidus casting + cooling slop, and then diecasting to produce the components. The main results are: 1) nodular and equi-axed crystal morphology was obtained at pouring temperature to diecasting machine 650 oC, colling length 300 mm and cooling slop 45 degrees; 2) Gas porosity is decreased remarkably, expressed in the increase of specific weight from 2,62 g/cm3 to 2,67 g/cm3, approaching the ASTM standard; 3) the research results were successfully applied to produce a thick-wall component, such as pump block, which are generally very difficult to produce by diecasting process.

Project at glance

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