DOI number:10.1016/j.matchar.2025.115803
Journal:Materials Characterization
Abstract:In this study, we aimed to suppress thermally-induced coarsening of 3 mol% yttrium-stabilized zirconia (3YSZ) nanograins through dopant segregation at grain boundaries (GBs). For this purpose, three dopants—Si, La, and Ca—were selected based on their potentially strong segregation tendencies. Three doping strategies were investigated: single-element doping (La), binary-element doping (Si and La), and ternary-element doping (Si, La, and Ca). The results indicated that a portion of the dopants dissolved within the ZrO2 grains as solute atoms, whereas the remainder segregated at GBs or accumulated at triple junctions in the form of a glassy phase. Although the ZrO2 grain sizes measured from SEM images were larger than those calculated using the Scherrer equation based on XRD results, the coarsening trends obtained from both methods were largely consistent. All three doping strategies demonstrated a coarsening inhibition effect during post-sintering thermal treatment up to 1250 °C, with the binary-element doping exhibiting the most pronounced inhibitory effect. This inhibition of coarsening can be attributed to the dual effects of doping: it not only kinematically restricts the diffusion of Zr and O atoms across GBs and exerts a drag force on GB movement, but also thermodynamically reduces the GB energy.
Co-author:Wenjun Yu, Zihua Lei, Mingxi Deng
First Author:Le Fu*
Correspondence Author:Yang Liu*
Volume:230
Page Number:115803
Translation or Not:no
Links to published journals:https://www.sciencedirect.com/science/article/pii/S1044580325010927