The process and mechanism of TiAl-Based alloy synthesized from Ti and Al powders

Abstract

The microstructures and elemental distribution of dense TiAl based alloy products produced by reactive-hot-pressing 1 : 1 Ti-Al blend powder were observed and analysed with scanning electron microscope (SEM). The four solid-state phases TiAl₃, TiAl, Ti₃Al andα-Ti were first formed in the original Ti particles through the reaction of Ti and Al according to the elemental distribution and their respective composition ranges. Then, the synthetic reactions continued among the four formed solid-state phases. With the diffusion and homogenization of elements, the formed TiAl₃ andα-Ti phases would disappear after further reacting. Finally, the microstructure consists of the two phases, TiAl and Ti₃Al.

Keywords

TiAl / reactive mechanism / reactive process / reactive-hot-pressing

References

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