The phase transformation behavior of freeze-dried 3 mol% yttria-partially-stabilized zirconia (3Y-PSZ) precursor powder has been studied. When the freeze-dried 3Y-PSZ precursor powder was calcined at 773-1073 K for 2 h, the crystalline structure was composed of tetragonal and monoclinic ZrO 2 as primary and secondary phases, respectively. The freeze-dried 3Y-PSZ precursor powder after calcination at 773 K, the monoclinic ZrO 2 content abruptly increased from 8.00% to 31.51% and the tetragonal ZrO2 content suddenly decreased from 92.00% to 68.49%, with the duration increasing from 0.5 to 1 min. The activation energy of the isothermal transformation from tetragonal to monoclinic was 7.02 kJ/mol. The kinetics equation for the phase transformation from tetragonal to monoclinic in the freeze-dried 3Y-PSZ precursor powder between 773 K and 1273 K for various durations is described as ln(1/1-α)=1/2.61[t2.61(1. 50×10-3)2.61exp(-7.02×103/RT)]; whereas, the HRTEM image shows a typical monoclinic ZrO2 domain because of the stress-induced tetragonal to monoclinic ZrO2 martensitic transformation that has occurred.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Process Chemistry and Technology
- Surfaces, Coatings and Films
- Materials Chemistry