Kinetics and microstructural evolution during recrystallization of a Ni3Al-based single crystal superalloy
(1. School of Materials Science and Engineering, Beihang University, Beijing 100191, China;
2. Key Laboratory of Aerospace Materials and Performance (Ministry of Education),
Beihang University, Beijing 100191, China;
3. Beijing Institute of Aeronautical Materials, Beijing 100095, China)
2. Key Laboratory of Aerospace Materials and Performance (Ministry of Education),
Beihang University, Beijing 100191, China;
3. Beijing Institute of Aeronautical Materials, Beijing 100095, China)
Abstract: The recrystallization kinetics and microstructural evolution of a Ni3Al-based single crystal superalloy were presented, especially the different recrystallization behaviors between the dendrite arm and the interdendritic region. The single crystal alloy was deformed by grit blasting. A succeeding annealing under inert atmosphere at 1280 °C for different time led to the formation of recrystallized grains close to the grit blasting surface. It was found that the recrystallization depth and velocity in the dendrite arm were respectively deeper and faster than those in the interdendritic region where the Y-NiMo phase existed. The recrystallization process in the interdendritic region was significantly inhibited by the Y-NiMo precipitates. However, the pinning effect gradually weakened with the annealing time due to the dissolution of the Y-NiMo phase, and the recrystallization depth in the dendrite arm was deeper than that in the interdendritic region.
Key words: recrystallization; kinetics; Y-NiMo phase; Ni3Al based single crystal superalloy