Hot oscillatory pressing of highly transparent Y ₂ O ₃ ceramics

Abstract In this work, the sintering behavior, microstructure, and transmittance of yttrium oxide (Y 2 O 3 ) ceramics prepared by hot pressing (HP) and hot oscillatory pressing (HOP) were compared. The results revealed that compared to HP, HOP enhanced the sinterability of Y 2 O 3 by increasing the densification rate and final density of the material. Meanwhile, the oscillatory pressure used in HOP generated much more dislocations distributed along grain boundaries in the resultant sample compared to the constant pressure used in HP. The high dislocation density triggered recrystallization upon post‐annealing of the sample prepared by HOP, which leading to the significant reduction of residual stresses and dislocation density. As a result, the annealed HOP‐prepared sample exhibited much higher transmittance than the counterpart prepared by HP, particularly in the visible light range.