Principal Investigator

Dr. Tran Duc Huy
Hanoi University of Science and Technology (HUST), Vietnam

ASEAN Co-Investigator

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Japanese Co-Investigator

Prof. Keiichi N.NISHIHARA
Kyoto University

Awarded year

2014

Program

Collaborative Research Program with Industry (CRI)

Field

Materials Engineering

Abstract

“. The use of titanium and its alloys has increased recently, because of their superior properties and improvements in machinability of these alloys. Main strengths of titanium-based alloys are their low density (nickel-based alloys are twice denser than titanium-based alloys), high strength at elevated temperatures, and high corrosion and creep resistance, as well as toughness, durability, and biological compatibility. But the only limited of titanium alloys is the cost and it still now mostly use in aerospace industry and some formula one racing car. The use of alloys based on TiAl and Ti3Al in the automotive components such as turbine rotors, blades of turbochargers and exhaust valves can provide benefits such as an increased power output and decreased fuel consumption of the reciprocal thermal automotive engines, which is vital to boost rotation speed and to reduce friction loss. The weight saving of the components is beneficial especially for the valves reciprocating at a high speed. The service temperature of the intake valves is under 10430C, so the conventional martensitic heat resistant steel can be replaced with Ti“6Al“4V. However, as the metal temperature of the exhaust valves reaches 13430C or higher, the modern material is indispensable to trim the weight and to ensure the high temperature strength equivalent to the austenitic heat resistant steel or Ni-base superalloys. In addition, the dimensions of the reciprocating valving train parts can be reduced. The success of high energy milling of raw materials TiO2 (ilmenite or rutile) and Al powder, subsequent with consolidation and sintering together with the exothermic reaction to form Ti-Al based matrix composite with nano scale in situ reinforcement Al2O3 opening a promising direct to reduce the cost of production since in order to get pure Ti must be used electrolytic or metallic reduction (such as magnesium). Depending on Al rich, the matrix can formed as follow reaction: 3TiO2 + 13Al †’3TiAl3 +2 Al2O3 (3) 3TiO2 + 5Al †’Ti3Al +2 Al2O3 (4) 3TiO2 + 7Al †’3TiAl +2 Al2O3 (5) “

Project at glance

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