Can a shape factor in bulk ceramics mitigate unwanted phase transformations?

The present work introduces the concept of 'shape strain' to illustrate its beneficial effect to control/avoid any undesired phase transition via consolidation/densification of ceramics; low (4 mole%)-doped ZrO2 ceramics with various dopants have been used for investigation. With ionic radii size difference (of dopant ion and Zr4+) above 30%, CaO-doped zirconia ceramics showed the effect most prominently. The effect was also dependent on the grain boundary mobility of dopants. Controlling final phase evolutions in ceramics is difficult and this effect may serve as remedy if tried with different size fractions of starting powders. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study introduces the concept of 'shape strain' to show its beneficial effect in controlling/avoiding undesired phase transitions in ceramics. The results indicate that CaO-doped zirconia ceramics exhibit the most prominent effect, which is also influenced by the dopant grain boundary mobility.