Dy2O3 stabilized ZrO2 as a toughening agent for Gd2Zr2O7 ceramic

摘要

3.5 mol% RE2O3 (RE=Dy, Y, Er, Yb) stabilized ZrO2 (RESZ) ceramics were synthesized by a chemical-coprecipitation and calcination method, and their phase composition and toughness were investigated. All the compounds consisted of metastable tetragonal (t') phase, and DySZ exhibited higher toughness than other RESZ ceramics. Gd2Zr2O7 added with x mol% (x=10, 20, 40, 60) DySZ ceramics were fabricated. Their toughness increased with the increase of the DySZ content. With the addition of 60 mol% DySZ, the compound had a toughness value of 1.82 M Pa m(1/2), approximately 1.15 times larger than that of Gd2Zr2O7. The toughening effect of DySZ for Gd2Zr2O7 was greater than that of YbSZ and YSZ, indicating that adding t'-ZrO2 based ceramic with higher toughness in Gd2Zr2O7 could improve the toughness better.