Elastic Properties of Stabilized HfO ² Compositions

Elastic moduli of several stabilized HfO 2 compositions were studied as functions of porosity and temperature. Thermal expansion was also measured for one of the compositions. The modulus vs porosity and thermal‐expansion measurements yielded typical relations. The modulus vs temperature measurements revealed an anomalous nonlinear relation between room temperature and 500°C. Varying microstructural and testing conditions had no effect on the nonlinearity. Only the percent of stabilizer additive caused any change in this behavior. It is proposed that oxygen‐vacancy motion is the probable cause of this behavior.