Phosphate glasses of composition 48P<sub>2</sub>O<sub>5</sub>-30CaO-(22<span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span&g...Phosphate glasses of composition 48P<sub>2</sub>O<sub>5</sub>-30CaO-(22<span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>x)Na<sub>2</sub>O-xTiO<sub>2</sub> (with 0 < x ≤ 3, mol%) were prepared by direct melting at 1080<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">°</span></span></span>C ± 20<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">°</span></span></span>C. The chemical durability of these glasses shows an improvement when the Ti<span style="white-space:normal;">O</span><sub style="white-space:normal;">2</sub> content varies from 0 to 2 mol%. The measurements of differential thermal analysis and density, both, indicate the increase of the glass transition temperature and the density. The increase of Tg leads to an improvement of glass rigidity. X-ray diffraction analysis of the glasses annealed at 650<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">°</span></span></span>C for 48 h, indicates the appearance of a mixture of metaphosphate and pyrophosphate phases when the Ti<span style="white-space:normal;">O</span><sub style="white-space:normal;">2</sub> content varies from 0 to 2 mol%, the last become majority when the Ti<span style="white-space:normal;">O</span><sub style="white-space:normal;">2</sub> content rich 2 mol%. Nevertheless, when the Ti<span style="white-space:normal;">O</span><sub style="white-space:normal;">2</sub> content exceeds 2 mol%, the analysis, both, by infrared spectroscopy and X-ray diffraction, reveals a radical change of structure with the formation of majorities isolated orthophosphate groups. SEM micrographs illustrated that the number of crystallites increased in the glass network when the Ti<span style="white-space:normal;">O</span><sub style="white-space:normal;">2</sub> content increased at the expense of the Na<sub>2</sub>O content. An increase in the TiO<sub>2展开更多
文摘Phosphate glasses of composition 48P<sub>2</sub>O<sub>5</sub>-30CaO-(22<span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>x)Na<sub>2</sub>O-xTiO<sub>2</sub> (with 0 < x ≤ 3, mol%) were prepared by direct melting at 1080<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">°</span></span></span>C ± 20<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">°</span></span></span>C. The chemical durability of these glasses shows an improvement when the Ti<span style="white-space:normal;">O</span><sub style="white-space:normal;">2</sub> content varies from 0 to 2 mol%. The measurements of differential thermal analysis and density, both, indicate the increase of the glass transition temperature and the density. The increase of Tg leads to an improvement of glass rigidity. X-ray diffraction analysis of the glasses annealed at 650<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">°</span></span></span>C for 48 h, indicates the appearance of a mixture of metaphosphate and pyrophosphate phases when the Ti<span style="white-space:normal;">O</span><sub style="white-space:normal;">2</sub> content varies from 0 to 2 mol%, the last become majority when the Ti<span style="white-space:normal;">O</span><sub style="white-space:normal;">2</sub> content rich 2 mol%. Nevertheless, when the Ti<span style="white-space:normal;">O</span><sub style="white-space:normal;">2</sub> content exceeds 2 mol%, the analysis, both, by infrared spectroscopy and X-ray diffraction, reveals a radical change of structure with the formation of majorities isolated orthophosphate groups. SEM micrographs illustrated that the number of crystallites increased in the glass network when the Ti<span style="white-space:normal;">O</span><sub style="white-space:normal;">2</sub> content increased at the expense of the Na<sub>2</sub>O content. An increase in the TiO<sub>2
