Details

Autor(en) / Beteiligte

• Shih, Yueh‐Ting
• Jean, Jau‐Ho

Titel

Mixed modifier effect in lithium‐calcium borosilicate glasses

Ist Teil von

• Journal of the American Ceramic Society, 2017-12, Vol.100 (12), p.5482-5489

Ort / Verlag

Columbus: Wiley Subscription Services, Inc

Erscheinungsjahr

2017

Quelle

Wiley Online Journals

Beschreibungen/Notizen

• The mixed modifier effect (MME) in the lithium‐calcium borosilicate glasses, which have a composition of 0.4[(1−x)Li2O–xCaO]–0.6[(1−y)B2O3–ySiO2] with x in the range of 0~1 and y in the range of 0.33~0.83, is investigated. The MME manifests itself as a positive deviation from linearity in the activation energy of electrical conductivity (Eaσ) and as a negative deviation from linearity in the fraction of four‐coordinated boron (N4), glass transition temperature (Tg), dilatometric softening temperature (Td), Vickers microhardness (Hv), dielectric constant (ε), and dielectric loss (tanδ). Moreover, the deviation, which exhibits a maximum at [CaO]/([CaO]+[Li2O])=0.5, is enhanced with increasing [SiO2]/[B2O3] ratio in the glass network. The observed MME in Tg, Td, and Hv are attributed to the bond weakening in the network; however, the MME in ε, tanδ, and Eaσ are caused by the obstruction of modifier transport in the glass network.