Abstract:Precipitation strengthening Ni-Fe based superalloy GH4169 has been widely used in aircraft engine, petroleum, nuclear industrial etc. Previous papers indicated that the phase transition from γ" to δ was performed when the temperature exceeded 650 oC. The reduction of strengthening phase amount degraded the mechanical properties and the application range. This paper summarized the characteristics of composition, microstructure and precipitated phases of GH4169 alloy. The influences of heat treatment and heat deformation process on the stability of microstructure and mechanical properties were reviewed, and the mechanical properties were affected by the morphologies and distribution of δ phase. The composition features of the modified alloy were concluded. In addition, the future trends and the possibility of GH4169 alloy to satisfy the use requirement for the 700 oC advanced ultra-supercritical power plants were proposed.