Fabrication and Characterization of TiAl Alloy by Fields Activated Sintering Technology (FAST)

Abstract

Ti-47Al alloy was fabricated by multi-physical fields activated sintering technology (FAST). With the coupling effects of electrical and pressure fields as the dominant driving force, a nearly full-density (relative density: 99.15%) TiAl alloy sample was obtained. The microstructural characterizations, phase transformation at different sintering temperatures and their contributions to mechanical properties were investigated. The results reveal that TiAl₃ is the main phase when sintered at 600 and 700 °C. When the sintering temperature reaches 800 °C, the main phases are TiAl and Ti₃Al. With the increase of sintering temperature, the content of TiAl increases and that of Ti₃Al decreases. When the sintering temperature reaches 1 000 °C, the alloy with fine and uniform microstructure and good mechanical properties can be obtained.

Keywords

TiAl alloy / Micro-FAST / Microstructure / Mechanical properties

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