Liquid‐phase sintering of ZrO₂‐based nanocrystalline glass–ceramics achieved by multielement co‐doping

Abstract

Liquid‐phase sintering (LPS) is an effective pathway to assist the densification of ceramics. However, it has seldom been used to densify glass–ceramics. In the present study, a multielement co‐doping strategy has been utilized to achieve LPS of a ZrO2–SiO2 nanocrystalline glass–ceramic. Compared with undoped samples densified by solid‐state sintering, doping of equimolar Al, Y, and Ca promoted the densification of the glass–ceramic at lower temperatures with a faster densification rate. Ternary doping enhanced coarsening of ZrO2 nanocrystallites during sintering and annealing. The distribution of dopants was carefully observed with X‐ray energy‐dispersive spectrometry technique in scanning electron transmission microscopy mode. Results showed that the three dopants showed different distribution behaviors. After sintering, Y dopants were predominately distributed in ZrO2 nanocrystallites, whereas parts of Al and Ca dopants were distributed in ZrO2 nanocrystallites and part of them co‐segregated at the ZrO2/SiO2 heterointerfaces. Meanwhile, the segregation of Ca dopant at some intergranular films among ZrO2 nanocrystallites was observed. Redistribution of dopants did not occur during annealing.

An effective strategy to inhibit grain coarsening: Construction of multi-element co-segregated grain boundary complexion

“…as-sintered samples were 193.5 nm, which was much larger than those in the as-sintered control group. This could be because eutectic phase with a low melting point was formed due to the addition of the multiple dopants, resulting in the occurrence of liquid phase sintering [43,44]. The occurrence of liquid phase sintering can be verified by comparing the densification curves of the undoped sample and the multi-element co-doped sample (Fig.…”

Zirconia‐containing glass‐ceramics: From nucleating agent to primary crystalline phase

“…The LPS sintering of glass-ceramics is interesting to follow to achieve full densification and modify the microstructure. 124…”

“…Therefore, the researchers tried to investigate the spatial distribution of ternary dopants (Al, Y, and Ca atoms) in the glass‐ceramic during sintering and crystallization. The LPS sintering of glass‐ceramics is interesting to follow to achieve full densification and modify the microstructure 124 …”

Additive Manufacturing of Zn‐Doped ZrO2 Architectures

“…[ 30 ] This is the segregation of dopants like Ca at intergranular films in ZrO 2 nanocrystallites. [ 31 ] Furthermore, incorporating dopants into ZrO 2 lattices can lead to changes in structural symmetry. The latter is the case for the homogeneous distribution of dopants in ZrO 2 , which increases bulk symmetry.…”