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 techni que using ultrasonic waves was used to determine the different parameters. Longitudinal and transverse wave velocities are measured by reflection meth od respectively at two frequencies: 10 and 5 MHz. The elastic modulus and P oisson's ratio were calculated from the measured ultrasonic velocities. The porosity dependence of the Poisson's ratio constitutes an originality as t his ratio is considered as constant in many papers. Moreover. the authors t ake into account the pore shape modification during the densification in Yo ung's modulus and Poisson's ratio calculations. (C) 2001 Elsevier Science L td. All rights reserved.