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Abstract The electrical conductivity behaviour of sodaflime silica glass tubes was studied during field-assisted ion exchange with molten salts of divalent cations. The molten salts used were ZnC12, SnC12, PbBr2 3 PbC12 and mixtures of PbC12/ CaC12, PbC12/ CaC12 and ZnC12 / BaC12. The field assisted ion exchange was carried out at constant temperature and potential in every experiment, while the current across the cell was recorded. The effect of the type of the metal cation exchanged, temperature and potential of exchange on the electrical conductivity of the glass were studied. The chemical composition of the exchanged glass surface was examined by several nondestructive techniques, to determine the concentration and penetration depth of the ion-exchanged cations. The techniques include Energy DispersiveX-ray Analysis (EDXA), X-ray fluorescence (XRF) and Rutherford Back-Scattering (RBS) . The surface ofc some glass tubes was photographed to illustrate the effect of ion-exchange process on the glass surf ace. This work was conducted to evaluate the phenomenolgoical model proposed by Hong and Cooper for divalent metal conductivity in soda-lime glass during field-assisted ion exchange, to study the factors which control the exchange process and to study the relation between the change in chemical composition of the glass surface and bulk conductivity of the glass during field-assisted ion exchange. |