Cation interdiffusion and phase stability in polycrystalline tetragonal ceria-zirconia-hafnia solid solution

Journal Article · Tue Oct 01 00:00:00 EDT 1991 · Journal of the American Ceramic Society; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1991.tb06808.x· OSTI ID:5877420

Sakka, Y; Oishi, Y; Ando, K; Morita, S ^[1]

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1. Kyushu Univ., Fukuoka (Japan). Faculty of Engineering

This paper reports on Zr-Hf interdiffusions that were carried out at 1350{degrees} to 1520{degrees} C for polycrystalline tetragonal solid solutions of 14CeO{sub c} {center dot} 86(Zr{sub 1{minus}x}Hf{sub x})O{sub 2} with X = 0.02 and 0.10. Lattice and grain-boundary interdiffusion parameters were calculated from the concentration distributions by using Oishi and Ichimura's equation. Lattice interdiffusion coefficients were described by D = 3.0 {times} 10{sup 3} exp({minus}623 (kJ/mol)/RT) cm{sup 2}/s and grain-boundary interdiffusion parameters by {delta}D{prime} = 0.29 exp({minus}506 (kJ/mol)/RT) cm{sup 3}/s. The cation diffusivity was lower than the anion diffusivity. The results were compared with diffusivities in the fluorite-cubic solid solution. The critical grain radii for stabilization of the tetragonal phase in CeO{sub 2}-doped ZrO{sub 2} were 11 and 6 {mu}m for the solutions with 2 and 10 mol% HfO{sub 2} substitution, respectively, both of which are much greater than in the Y{sub 2}O{sub 3}-doped ZrO{sub 2} solid solution.

• OSTI ID: 5877420
• Journal Information: Journal of the American Ceramic Society; (United States), Journal Name: Journal of the American Ceramic Society; (United States) Vol. 74:10; ISSN JACTA; ISSN 0002-7820
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
CATIONS
CERIUM COMPOUNDS
CERIUM OXIDES
CHALCOGENIDES
CHARGED PARTICLES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTALS
DIFFUSION
DISPERSIONS
GRAIN BOUNDARIES
GRAIN SIZE
HAFNIUM COMPOUNDS
HAFNIUM IONS
HAFNIUM OXIDES
IONS
MICROSTRUCTURE
MIXTURES
OXIDES
OXYGEN COMPOUNDS
PHASE STUDIES
POLYCRYSTALS
RARE EARTH COMPOUNDS
REFRACTORY METAL COMPOUNDS
SIZE
SOLID SOLUTIONS
SOLUTIONS
STABILITY
TEMPERATURE RANGE
TEMPERATURE RANGE 1000-4000 K
TETRAGONAL LATTICES
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS
ZIRCONIUM IONS
ZIRCONIUM OXIDES