期刊
INTERNATIONAL JOURNAL OF APPLIED GLASS SCIENCE
卷 13, 期 1, 页码 121-134出版社
WILEY PERIODICALS, INC
DOI: 10.1111/ijag.16505
关键词
crucible dissolution; Niobate in glasses; optical basicity; phosphate and silicate glasses; Raman spectroscopy
资金
- ARGENTUM TRIGGERING RESEARCH GRANTS -'Excellence Initiative -Research University' [DEC-19/2020/IDUB/I.3.3]
- VINNOVA [2015-04809]
- Stiftelsen for Kunskaps-och Kompetensutveckling [68110029]
- Crafoord Foundation [20160900]
- European Union [MIS 5002409]
Using niobium crucibles for melting glasses with different modifier oxide contents led to varying dissolution rates of niobate, detectable in Raman spectra even at low concentrations. Silica-rich glasses showed minimal Nb dissolution, while higher basicity metasilicate and pyrophosphate glasses exhibited characteristic niobate signatures. The tendency of melts to dissolve Nb crucible was discussed in relation to network connectivity, polymerization, and melt viscosity.
Using niobium crucibles for melting phosphate and silicate glasses of various modifier oxide contents, and therefore varying optical basicity (Lambda), was found to result in varying dissolution rates of niobate during melting. Because of their high electronic polarizability, even small concentrations of niobates are detectable in the Raman spectra of glasses. Even <1 mol% Nb2O5 can be identified, as independently confirmed by SEM-EDX analysis. Silica-rich glasses (similar to 60% SiO2, Lambda similar to 0.6) did not show significant Nb dissolution from the crucible, while higher basicity metasilicate glasses (similar to 50% SiO2, Lambda similar to 0.65) and pyrophosphate glasses (similar to 30% P2O5, Lambda similar to 0.7) did show the typical niobate signature in the Raman spectra at 810-840 cm(-1), depending on composition. While niobium is well-dissolved throughout the pyrophosphate glass, metasilicate glasses showed a much more intense Raman signature of niobate units near the outer surface of the glass. Measurements along the cross-section of a fractured metasilicate glass showed a steady decrease of the strength of the niobate signature from the surface toward the bulk of the material. Besides correlation with optical basicity, the tendency of melts to dissolve Nb crucible was discussed in terms of the connectivity or polymerization of the network and the corresponding melt viscosity.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据