The high-temperature creep resistance in Al2O3 is improved greatly by ZrO2 doping. Zirconium ions are found to be segregated in Al2O3 grain boundaries. The activation energies for creep in high-purity Al2O3 and ZrO2-doped Al2O3 are estimated to be 430 and 650 kJ mol-1 respectively. The grain boundary diffusivity of Al ions is expected to be reduced by the segregation of Zr4+ in the grain boundaries.
ASJC Scopus subject areas
- Condensed Matter Physics