Influence of delta phase precipitation on static recrystallization of cold-rolled Inconel 718 alloy in solid solution treatment

Due to the improvement in fatigue strength of cold-rolled blades,the static recrystallization behavior of cold-rolled Inconel 718 alloy in the solid solution treatment was investigated with the methods of optical microscopy and electron backscattered diffraction.The effect ofδphase precipitation on the static recrystallization process was also analyzed.The results show thatδphase preferentially precipitates comparing to static recrystallization.Affecting by theδphase preferential precipitation process,sub-grain migration is the main nucleation mechanism in the static recrystallization of coldrolled Inconel 718 alloy at 980°C.Meanwhile,strain-induced boundary migration also exists as an aided nucleation mechanism when the rolling reduction is less than 30%.