Mixed-alkali effect in the dilute foreign-alkali region. Failure of the strong electrolyte/cationic interaction model

Journal Article · Tue Jul 01 00:00:00 EDT 1980 · J. Am. Ceram. Soc.; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1980.tb10212.x· OSTI ID:5202857

Moynihan, C T; Saad, N S; Tran, D C; Lesikar, A V

Electrical conductivity and relaxation data were measured for glasses of composition 0.242(XK/sub 2/O+(1-X)Na/sub 2/O) - 0.758SiO/sub 2/ from 25/sup 0/ to 205/sup 0/C and in the dilute Na+ ion composition range X = 0.9 to 1. The decrease in electrical conductivity sigma when the majority alkali K+ is replaced with the foreign alkali Na+ is most rapid in the very dilute range X = 0.98 to 1 and becomes less rapid at larger Na+ contents. The electric field relaxation times agree well with the single-alkali mechanical relaxation times. The electric field relaxation function becomes more exponential with increasing foreign alkali content, indicating a corresponding decrease in the concentration of mobile ions. Attempts to account for the decrease in sigma with increasing foreign alkali content by assuming that the single-alkali glass is a strong electrolyte and that the foreign alkali complexes with and immobilizes the majority alkali were unsuccessful. Calculated values of the number of majority alkali ions complexed by a foreign-alkali ion were unreasonably large.

• Research Organization: Catholic Univ. of America, Washington, DC
• OSTI ID: 5202857
• Journal Information: J. Am. Ceram. Soc.; (United States), Journal Name: J. Am. Ceram. Soc.; (United States) Vol. 63:7-8; ISSN JACTA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ACTIVATION ENERGY
ALKALI METAL COMPOUNDS
CHALCOGENIDES
DIFFUSION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ENERGY
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
POTASSIUM COMPOUNDS
POTASSIUM OXIDES
RELAXATION
SELF-DIFFUSION
SILICON COMPOUNDS
SILICON OXIDES
SODIUM COMPOUNDS
SODIUM OXIDES