TiAl-base alloys exhibit outstanding balanced mechanical properties at high temperatures

which are considered as important light-weight structural candidates within 650-1000℃ in aerospace industry. The microstructures of TiAl alloys are unstable and decompose at evaluated temperatures

which would affect the mechanical properties. Therefore

the thermal stability and the microstructural evolution and the influence on properties have attracted close attentions for a long time. In this paper

the connotation of thermal stability of TiAl-base alloys is introduced. The microstructures evolution and phase transition of TiAl-base alloys under high temperature conditions are discussed and analyzed

including the discontinuous coarsening of α2/γ lamella and the continuous coarsening of γ lath strip

the decomposition of α2 phase and the change of B2 (ω) phase. The effects of temperature

time

alloying elements and thermal load on microstructures

thermal stability and mechanical properties of TiAl alloy are summarized and summarized. Finally

the research direction of thermal stability of TiAl alloy is summarized and forecasted.