To study the precipitation dynamics ofδphase in Inconel 718alloy,two-stage interrupted compression method was used in the region of cold deformation temperatures and the temperatures range from 875to 975℃.The precipitation-time-temperature(PTT)curve ofδphase was obtained by analyzing the softening kinetics curves.For verifying the type of the precipitates and confirming the validity of the test,the transmission electron microscopy(TEM),scanning transmission electron microscopy(STEM)and energy dispersion spectrum(EDS)were employed.Experimental results indicated that the PTT curve forδprecipitation exhibited a typical“C”shape and the nose points of start and finish precipitation were about 5sat 920℃and 2 815sat 940℃,respectively.In addition,the nucleation ofδwas heterogeneous.The nucleation sites varied with temperatures,including dislocation,grain boundary and stacking fault withinγ″phase.Andδparticles grew quickly at higher temperature with lower density.Moreover,the driving force of nucleation was mainly including chemical free energy,interfacial energy and dislocation distorted energy.And the dislocation distorted energy could decide the density of nucleation in the strain-induced process. To study the precipitation dynamics of δphase in Inconel 718 alloy, two-stage interrupted compression method was used in the region of cold deformation temperatures and the temperatures range from 875 to 975 ° C. The precipitation-time-temperature (PTT) curve of δphase was obtained by analyzing the For softening kinetics curves. For verifying the type of the precipitates and confirming the validity of the test, the transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM) and energy dispersion spectrum (EDS) were employed. Experimental results indicated that the PTT curve for δprecipitation exhibited a typical “C ” shape and the nose points of start and finish precipitation were about 5sat 920 ° C and 2 815sat 940 ° C, respectively. In addition, the nucleation of δwas heterogeneous. nucleation sites varied with temperatures, including dislocation , grain boundary and stacking fault within γ "phase. Andδparticles grew quickly at higher temperature with lower density. Moreover, the dr iving force of nucleation was mainly including chemical free energy, interfacial energy and dislocation distorted energy. And the dislocation distorted energy could decide the density of nucleation in the strain-induced process.