Infrared spectra in nonstoichiometric yttria-stabilized zirconia mixed crystals at elevated temperatures

Infrared (IR) reflectivity measurements were undertaken on pure ZrO2 and stabilized ZrO2xY2O3 solid solutions containing 3-, 4-, 7-, 12-, and 20-wt.% Y2O3 over 10--900 cm-1 region as a function of temperature up to 1400 0C. The observed IR active phonons are related to the phase transitions that depend on composition and temperature. Good agreement was achieved among IR, Raman scattering, and neutron scattering investigations. An IR reflectivity enhancement from 42% to 60% in the low-frequency region (10--110 cm-1) was found as the monoclinic(M)-tetragonal(T) martensitic transition was completed in pure ZrO2 and ZrO2x3-wt.% Y2O3