The study on interaction mechanisms between Ti48Al2Cr2Nb alloy and Y2O3 ceramic crucibles with good thermal shock resistance: Assessing a novel, cost-effective approach to the preparation of high-performance TiAl alloys

Abstract

Enhancing the thermal shock resistance of Y2O3 ceramic crucibles, coupled with advancements in melting and casting technologies to reduce the adverse influence of interfacial reactions, is essential for producing low-energy consumption, high-quality titanium-aluminum (TiAl) alloys. In this study, the Y2O3 ceramic crucible with good thermal shock resistance was developed through the optimization of particle size distribution and sintering holding time. The interaction mechanisms between Y2O3 ceramics and TiAl alloys under extreme conditions were investigated, and strategies for enhancing the mechanical properties of TiAl alloys through the integration of Y2O3 crucibles with centrifugal casting were discussed. The results indicated that introducing large particles of 1–3 mm under sintering conditions of 2023 K and 6 h effectively enhances the thermal shock resistance of Y2O3 crucible. The interaction between Y2O3 and TiAl alloys primarily involved physical erosion (spalling/dispersion), dissolution of separated particles, and surface modification of interface layer particles (reaction). Physical erosion played an important role in this dynamic interaction, with the extent of erosion intensifying through continuous use of the crucible, while electromagnetic forces ensured the uniform distribution of inclusions within the TiAl alloy matrix. Moreover, the application of centrifugal casting technology substantially refines the grain size and reduces the inclusion count, thereby significantly enhancing the mechanical properties of TiAl alloy.