Comment on “Effect of Interface Structure on the Microstructural Evolution of Ceramics”

Demystifying the role of sintering additives with “complexion”

“…[31][32][33][34][35][36] Despite much progress, however, fundamental mechanisms are still debated even after 50 years of continuous study. 37 Two examples of this are the mechanism(s) for abnormal grain growth, and the classic debate over the role of magnesia as a sintering aid. [37][38][39] However, the recent discovery of interface "complexions" offers a new perspective and possible solution to such problems.…”

“…37 Two examples of this are the mechanism(s) for abnormal grain growth, and the classic debate over the role of magnesia as a sintering aid. [37][38][39] However, the recent discovery of interface "complexions" offers a new perspective and possible solution to such problems. 40,41 Interface complexions are equilibrium interface 'phases' that have associated thermodynamic properties.…”

Reply to the Comment on “Effect of Interface Structure on the Microstructural Evolution of Ceramics”

“…One of them is the liquid‐phase scavenger 10 . It is well known that the addition of magnesia changes wetted interfaces to non‐wetted ones as mentioned in the comment by Dillon and Harmer 1 as well as in our paper 2 . For this reason, the liquid phase tends to be absent in magnesia‐doped alumina.…”

“…T he comment 1 raised some important questions and ambiguities on some part of the discussions in our previous paper 2 . The purpose of this reply is to make these questions and ambiguities clear.…”

“…Because of this cross‐sectioning issue, the large grain presented in Fig. 1 in the comment 1 is not an appropriate evidence for the claim that a grain consisting exclusively of curved interfaces can undergo abnormal grain growth.…”