High temperature properties of ZnO ceramics studied by the impulse excitation technique

This study reports on impulse excitation technique (IET) measurements up to 900 °C in air performed on various grades of ZnO ceramics, containing bismuth and antimony oxides as dopants. The IET provides dynamic elastic (E-modulus) and damping properties as a function of temperature. In order to correlate the IET behaviour with the microstructure and phase evolution, SEM and high temperature XRD (HT-XRD) analysis were carried out. Damping peaks related to phase transitions were observed in the samples containing Bi2O3 intergranular phase. Three other peaks are tentatively interpreted as point defect relaxations.