Fast firing of 3 mol% yttria‐stabilized zirconia: On the effect of heating rate on sintering

The impact of rapid heating on sintering is currently getting a growing scientific interest. Previous results have shown that when considering 90 nm-sized 3 mol% yttria-stabilized zirconia (3YSZ) powder the heating rate effect on densification is not detectable, whereas it is huge when using finer powder (≈20 nm, specific surface area, SSA = 30–60 m2 g−1). Herein, we investigate the fast firing of ≈40 nm 3YSZ powder (SSA = 16 m2 g−1) and compare it with conventional sintering. The results show that the heating rate has a modest effect on the final density with improvements always below 2%–3% in terms of relative density. The relatively good match between fast firing and the densification behavior predicted by the master sintering curves agrees with the observed microstructural evolution, where fast-firing provides only a modest effect on the pore size. Finally, it is shown that the heating rate does not impact the dynamics of closed pore formation. © 2024 The American Ceramic Society.