Abstract
Na5YSi4O12 has been prepared from spray-frozen/freeze-dried precursor powders calcined at 620°C for three hours. Sintering at 1140°C for 30 minutes gave a ceramic of 97.7% theoretical density. The material was single phase NYS with a 300°C resistivity of 6.5 Ωcm, an activation energy for Na+ ion conduction of 20.1 kJ/mol, a flexural strength of 75 MPa, a duplex fine grain structure of (0.1–3μm) and a constant linear thermal expansion coefficient (25–470°C) of 13.1 × 10−6/°C ±5%. The properties of the NYS ceramics are especially sensitive to small soda deficiencies.
Original language | English |
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Journal | Materials Research Bulletin |
Volume | 17 |
Issue number | 4 |
Pages (from-to) | 541-548 |
ISSN | 0025-5408 |
DOIs | |
Publication status | Published - 1982 |
Externally published | Yes |