Temperature Dependence of the Elastic Moduli, Dilational and Shear Internal Frictions and Acoustic Wave Velocity for Alumina, (Y)TZP, β′-Sialon and α-SiC Ceramics

Abstract

Young, shear and bulk moduli and Lamé parameters, and Poisson's ratio of β′-sialon, alumina, (Y)TZP and α-SiC decrease and increase with increasing of temperature, respectively, suggesting activation of shear mode in a high temperature region. The high-temperature shear internal friction for (Y)TZP and sialon are more sensitive to relief of strain and softening of glassy phase at grain boundaries, respectively, compared with the dilational one. Rapid increase in dilational friction corresponds to grain boundaries sliding phenomena such as superplasticity and recrystallization.