Influence of porosity on Young's modulus and Poisson's ratio in alumina ceramics

This work presents a study on the influence of the porosity level on Young's modulus and Poisson's ratio of sintered alumina. A non-destructive technique using ultrasonic waves was used to determine the different parameters. Longitudinal and transverse wave velocities are measured by reflection method respectively at two frequencies: 10 and 5 MHz. The elastic modulus and Poisson's ratio were calculated from the measured ultrasonic velocities. The porosity dependence of the Poisson's ratio constitutes an originality as this ratio is considered as constant in many papers. Moreover. the authors take into account the pore shape modification during the densification in Young's modulus and Poisson's ratio calculations. (C) 2001 Elsevier Science Ltd. All rights reserved.