Order-disorder transition and thermal conductivity of (Yb x Nd1− x )2Zr2O7 solid solutions

• Published in: Philosophical magazine (Abingdon, England) Vol. 89; no. 6; pp. 553 - 564
• Main Authors: Liu, Z.-G., Ouyang, J.-H., Zhou, Y., Meng, Q.-C., Xia, X.-L.
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis Group 01-02-2009; Taylor & Francis
• Subjects: Condensed matter: structure, mechanical and thermal properties; disorder; Equations of state, phase equilibria, and phase transitions; Exact sciences and technology; General studies of phase transitions; Inorganic compounds; order; Order-disorder and statistical mechanics of model systems; phase transitions; Physics; structure analysis; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; thermal properties; Temperature dependence; Order-disorder transformations; Transmission electron microscopy; Mean free path; Solid solutions; Thermal conductivity; XRD; Pyrochlore type compound; Defects; Crystal structure
• ISSN: 1478-6435; 1478-6443
• DOI: 10.1080/14786430802684126

X-ray diffraction, transmission electron microscopy and a laser-flash method were used to investigate the order-disorder transition and thermal conductivity of (Yb
x
Nd
1−
x
)
2
Zr
2
O
7
(0 ≤ x ≤ 1.00) solid solutions. The structures were found to be pyrochlore-type for 0 ≤ x ≤ 0.25, defect fluorite for 0.45 ≤ x ≤ 1.00 and a mixture of these at 0.30 ≤ x ≤ 0.40. The thermal conductivities of (Yb
x
Nd
1−
x
)
2
Zr
2
O
7
first gradually decrease with increasing temperature, and then increase slightly above 800°C due to the increased radiation contribution. YbNdZr
2
O
7
has the lowest thermal conductivity due to the reduced cation mean free path at the compositional combination of equal molar Yb
3+
and Nd
3+
cations.