Study of sintering mechanisms of Ca-doped yttrium aluminum garnet ceramics: From nanostructure to macroscopic behaviour

Effect of CaO doping on densification and microstructure control of highly transparent La0.4Gd1.6Zr2O7 ceramics

“…This rise most likely indicates that the solubility limit of Ca 2+ in the ordered pyrochlore structure is reached. 27 Therefore, the results suggest that the Ca 2+ ions have been effectively incorporated into the La 0.4 Gd 1.6 Zr 2 O 7 lattice. The substitute limits might be influenced by the charge difference between Ca and La.…”

“…Then, a slight increase is plotted with more CaO concentration. This rise most likely indicates that the solubility limit of Ca 2+ in the ordered pyrochlore structure is reached 27 . Therefore, the results suggest that the Ca 2+ ions have been effectively incorporated into the La 0.4 Gd 1.6 Zr 2 O 7 lattice.…”

“…But for the C 0.10 series samples, the average grain size decreased to 10.17 μm, which might be contributed to the solute drag effect. The previous report has demonstrated that whatever its content, calcium segregates at grain boundaries of YAG ceramics 27 …”

“…The previous report has demonstrated that whatever its content, calcium segregates at grain boundaries of YAG ceramics. 27 Actually, Zhang et al has also demonstrated the "density promotion" and the "solute drag" effects of CaO doping with respect to the densification process of ceramics exhibited a competitive relationship. 32 A small amount of Ca doping can accelerate the rate of grain boundary migration and densification, which may be explained by the following defect analysis.…”