Effect of variation in framework composition on the thermal expansivity of NZP phases

Journal Article · Sat Oct 01 04:00:00 EDT 1994 · Materials Research Bulletin; (United States)

DOI:https://doi.org/10.1016/0025-5408(94)90081-7· OSTI ID:6886867

Kutty, K V.G.; Asuvathraman, R; Mathews, C K ^[1]; Varadaraju, U V ^[2]

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1. Indira Gandhi Centre for Atomic Research, Kalapakkam (India). Materials Chemistry Division
2. Indian Inst. of Technology, Madras (India). Materials Science Research Centre

Two series of NZP compounds, NaM[sub 2](PO[sub 4])[sub 3] and NbM(PO[sub 4])[sub 3] [M = Ti, Zr, Hf, Sn and Th] have been synthesized and their thermal expansion coefficients in the temperature range 298--1,273 K determined by using high temperature x-ray powder diffractometry. In the first series, the influence of the M-O bond is clearly seen even in the presence of the large contribution of the Na-O bond to thermal expansion; the expansively of the lattice is found to vary with the ionic radius of the M atom. This trend is also reflected in the infra-red absorption frequencies of these compounds. In the second series, while the expansion behavior is found to be dependent on M, the variation of expansively with M is different from that found in the first series. The tin compounds in both the series display anomalous behavior. The authors also report here, for the first time, a phase transformation in NbSn(PO[sub 4])[sub 3] around 673 K characterized by a maximum and a minimum in the lattice parameters a and c respectively.

• OSTI ID: 6886867
• Journal Information: Materials Research Bulletin; (United States), Journal Name: Materials Research Bulletin; (United States) Vol. 29:10; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602 -- Other Materials-- Structure & Phase Studies
360606* -- Other Materials-- Physical Properties-- (1992-)
ACTINIDE COMPOUNDS
ALKALI METAL COMPOUNDS
CRYSTAL STRUCTURE
DATA
EXPANSION
EXPERIMENTAL DATA
HAFNIUM COMPOUNDS
HAFNIUM PHOSPHATES
INFORMATION
LATTICE PARAMETERS
NIOBIUM COMPOUNDS
NIOBIUM PHOSPHATES
NUMERICAL DATA
OXYGEN COMPOUNDS
PHOSPHATES
PHOSPHORUS COMPOUNDS
REFRACTORY METAL COMPOUNDS
SODIUM COMPOUNDS
SODIUM PHOSPHATES
THERMAL EXPANSION
THORIUM COMPOUNDS
THORIUM PHOSPHATES
TIN COMPOUNDS
TIN PHOSPHATES
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS
ZIRCONIUM PHOSPHATES