Densification behavior of Spark Plasma Sintered La2O3–YSZ ceramic composites

The present paper describes the fabrication and densification behavior of 8 mol% Yttria-stabilized Zirconia (YSZ)-based composites with the addition of 11.6, 21.6 and 30.5 wt% La2O3 fabricated by the Spark Plasma Sintering (SPS) process. Addition of La2O3 to YSZ had a significant grain refining effect on the YSZ ceramic. In all of the studied composites, the desirable cubic structure of the YSZ matrix was retained and 94–96% densification was achieved. The matrix of the sintered composites evolved a solid solution due to interdiffusion of La, Zr and Y, as well as formation of pyrochlore lanthanate La1.6Y0.4Zr2O7 phase formed as the reaction product between YSZ and La2O3 during sintering.