Evaluation of Elastic Property of (CeO₂)_1-x(YO_1.5)_x Ceramics

Abstract

The influences of the sintering additive content of Y₂O₃ on elastic modulus of ceria ceramics were investigated by small punch (SP) testing method and molecular dynamics (MD) method. Y₂O₃ doped ceria powders with a composition of (CeO₂)_1-x(YO_1.5)_x (x=0, 0.10, 0.15, 0.20, 0.30, 0.40) were prepared by a co-precipitation method. The powders were compacted by die pressing (50 MPa) followed by cold isostatic pressing (120 MPa), and sintered at 1500°C in air for 5 h. The elastic modulus was decreased significantly with increasing additive contents of the Y₂O₃ oxides. Especially, it tended to exhibit a minimum value at 10∼20 mol%. However, ionic conductivity increased with increasing additive content of the Y₂O₃ oxides, exhibited a maximum value at 15 mol%. Calculation model and interatomic potential were shown to be useful to evaluate the elastic property.