Title of article :
In recent years, growing demand for greater mechanical properties of PM steel components with competitive fabrication cost has led to significant innovations in different fields of powder metallurgy. Recent research has been focused on reaching higher per
Author/Authors :
Cui Renjie، نويسنده , , Gao Ming، نويسنده , , Xian-Zhang Hu، نويسنده , , Gong Shengkai، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2010
Abstract :
In this work, U-shaped yttria ceramic crucibles have been prepared to melt Ti–47Al (at.%) alloy in a vacuum induction furnace, in order to simulate the worst practical situation with respect to the interactions between TiAl alloy and yttria refractory material. The effects of superheating temperature and cooling media on the metal–crucible interface, microstructure, chemical composition and microhardness have been evaluated. The investigation demonstrates that interactions between the yttria crucible and the molten TiAl consist of slight chemical dissolution and some physical erosion and the extent of the dissolution and erosion depend on the superheating temperature. The thermodynamics of TiAl–Y2O3 reactions have been investigated according to the calculation of the Gibbs free energy change of the yttria dissolution reaction. The possibilities of melting and casting TiAl alloys by the use of yttria refractory material are also discussed.
Keywords :
Titanium aluminides , Intermetallics , Casting , Microstructure , Thermodynamic analysis
Journal title :
Journal of Materials Processing Technology
Journal title :
Journal of Materials Processing Technology