Effects of annealing on microstructures and properties of cold-rolled GH3536 sheet

Abstract

In this study, the effects of annealing on microstructures and the properties of GH3536 superalloy sheets were studied in detail by means of Electron Backscatter Diffraction (EBSD), Scanning Election Microscopy (SEM) and Transmission Electron Microscopy (TEM). The results show that a series of phenomena happened after annealing at 950 °C. The recrystallization occurs when the alloy is annealed at 950 °C, and new strain-free grains replace the strained grains. There is a significant reduction in grain size, low-angle grain boundaries and dislocation density. Meanwhile, a mass of M 6 C carbides precipitate along grain boundaries after annealing at 950 °C. And a large number of annealing twins are also formed during this process. The reduction of dislocation density due to the recrystallization of the alloy leads to a noteworthy decrease in strength and an obvious increase in plasticity, which means excellent reprocessing ability are obtained after recrystallization. • The recrystallization temperature of GH3536 superalloy is obtained. • Amounts of annealing twins are formed in the stage of recrystallization. • Increased recrystallized fraction was linked to excellent reprocessing ability. • Higher ductility and lower strength are developed through annealing treatment.