Effects of heat treatment on the microstructure and mechanical properties of Ni3Al-based superalloys: A review

Ni3Al-based alloys have drawn much attention as candidates for high-temperature structural materials due to their excellent comprehensive properties. The microstructure and corresponding mechanical properties of Ni3Al-based alloys are known to be susceptible to heat treatment. Thus, a significant step is to employ various heat treatments to derive the desirable mechanical properties of the alloys. This paper briefly summarizes the recent advances in the microstructure evolution that occurs during the heat treatment of Ni3Al-based alloys. Aside from gamma ' phase and gamma phase, the precipitations of beta phase, alpha-Cr precipitates, and carbides are also found in Ni3Al-based alloys with the addition of various alloying elements. The evolution in morphology, size, and volume fraction of various types of secondary phases during heat treatment are reviewed, involving gamma ' phase, beta phase, alpha-Cr precipitate, and carbides. The kinetics of the growth of precipitates are also analyzed. Furthermore, the influences of heat treatment on the mechanical properties of Ni3Al-based alloys are discussed.

Automated summary

The heat treatment of Ni3Al-based alloys significantly influences the microstructure of the alloys and desirable mechanical properties can be achieved through heat treatment. Additionally, the evolution of secondary phases during heat treatment, including the kinetics of precipitate growth, and the effects of heat treatment on the mechanical properties of the alloys are discussed.