Premium
Phase Formation in the System ZrO 2 –LaO 1.5 –MnO x in Air and P ∼1 Pa After 500 h of Annealing at 1200° and 1400°C
Author(s) -
Chatzichristodoulou Christodoulos,
Chen Ming,
Bowen Jacob R.,
Liu YiLin
Publication year - 2010
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2010.03774.x
Subject(s) - tie line , annealing (glass) , phase diagram , materials science , phase (matter) , crystallography , line (geometry) , diffraction , electron diffraction , chemistry , metallurgy , thermodynamics , optics , physics , geometry , organic chemistry , power (physics) , electric power system , mathematics
The phase relation in the ZrO 2 –LaO 1.5 –MnO x system has been experimentally determined at 1200° and 1400°C in air and at 1200°C in N 2 ( ∼10 0 Pa). Tie lines between LaMnO 3 and t ‐ZrO 2 and between LaMnO 3 and La 2 Zr 2 O 7 are observed at 1200°C in air. The geometry of the phase diagram changes at 1400°C in air due to the appearance of a stabilized ZrO 2 phase, found to be of cubic symmetry by backscattered electron diffraction. Tie lines of LaMnO 3 – c ‐ZrO 2 , LaMnO 3 –La 2 Zr 2 O 7 , and c ‐ZrO 2 –La 2 Zr 2 O 7 are observed. At 1200°C in N 2 ( ∼10 0 Pa), the LaMnO 3 – t ‐ZrO 2 tie line observed at 1200°C in air is replaced by the La 2 Zr 2 O 7 –MnO tie line. Stabilization of c ‐ZrO 2 is observed and a new compound forms, which is being reported for the first time. The proposed composition of the new compound is La 2 Zr 5 MnO 14+δ .