Abstract: Superalloys have been used for many years in the aerospace industry due to their excellent creep performance in high temperature and high stress environments. The precipitation that contributes to creep resistance also increases the strength; however, this gives rise to thermomechanical processing issues. Therefore, the ultimate goal of this work is to understand the precipitation characteristics in order to design heat treatments that make thermomechanical processing easier without compromising the final microstructure and properties. The main precipitate that was examined was the gamma prime phase (γ’) [Ni3 (Al,Ti)], which largely determines the mechanical properties of the alloy. The γ’ was found to form in three different sizes; primary, secondary and tertiary. The differences in the volume fraction and morphology of each precipitate type was noted and the relationship between heat treatment and precipitates will be discussed.
Authors: C.M. Katsari, H. Che, B. Turner, A. Wessman, and S. Yue
Keywords: Gamma Prime, Nickel-Based Superalloy, Heat-Treatment, Precipitation