High-temperature titanium alloys are one of the most important research directions in the field of high-temperature aerospace alloys. They are mainly used in high-temperature-resistant components, such as blade disks, blades, and casings of aero-engines, and are key materials in a new generation of high thrust-to-weight ratio aero-engines. In the service environment of engineering applications, the creep resistance of high-temperature titanium alloys is one of the most important characteristic indicators. This paper reviews and analyzes the research status and progress on the creep properties of typical high-temperature titanium alloys in service in recent years. The effects of the creep parameters, alloy composition, and microstructure on the creep behavior of high-temperature titanium alloys are discussed, and various possible mechanisms for increasing the creep resistance of high-temperature titanium alloys are summarized.

The microstructure and room temperature tensile properties of heat-treated TC25G alloy after thermal exposure were investigated. The results show that the α₂ phase dispersed in the α phase, and silicide precipitated firstly at the α/β phase boundary and then at the dislocation of the α_p phase and on the β phase. When thermal exposure was 0–10 h at 550 °C and 600 °C, the decrease of alloy strength was mainly due to the dominant effect of dislocations recovery. With the rise and extension of thermal exposure temperature and time, the increasing quantity and size of precipitates played an important role in the improvement of alloy strength. When thermal exposure temperature rose to 650 °C, the strength was always lower than that of heat-treated alloy. However, since the decreasing rate of solid solution strengthening was smaller than the increasing rate of dispersion strengthening, alloy still showed an increasing trend in the range of 5–100 h. When thermal exposure time was 100–500 h, the size of the α₂ phase increased from the critical value of 3 nm to 6 nm, and the interaction between the moving dislocations and the α₂ phase changed from the cutting mechanism to the by-pass mechanism (Orowan mechanism), and thus alloy strength decreased rapidly.