Thermophysical Properties and Sintering of Ytterbia-Stabilized Tetragonal Zirconia Ceramic

Graphical Metastable tetragonal (t′) ZrO 2 stabilized with 4 mol% Yb 2 O 3 sinters more slowly and has a higher resistance to destabilization than YSZ with the same composition (4 mol% Y 2 O 3 ). The improved phase stability is attributed to the slower diffusion of the smaller Yb 3+ ion in t′ phase compared to the larger Y 3+ ion. In addition, the TEC of 4 mol% Yb 2 O 3 -stabilized ZrO 2 is also found to be superior to that of YSZ, suggesting practical possibility for thermal barrier coatings.