In order to improve the bending strength of mullite ceramic thin tiles, SiO2-ZnO-Na2O-Y2O3 glass was prepared on the surface of the tiles. The influences of the thermal properties and thermal expansion coefficient of ...In order to improve the bending strength of mullite ceramic thin tiles, SiO2-ZnO-Na2O-Y2O3 glass was prepared on the surface of the tiles. The influences of the thermal properties and thermal expansion coefficient of the glass and the sintering temperature on the structure and the property of the composites were investigated by differential thermal analysis (DTA), X-Ray Diffraction (XRD), Raman and scanning electron microscopy (SEM). The bending strength of the composites was measured with an universal testing machine. Results show that the crystallization temperature of the SiO2-ZnO-Na2O-Y2O3 glass is higher than that of SiO2-ZnO-Na2O glass. The corresponding crystallites show more complex structure for the SiO2-ZnO-Na2O-Y2O3 glass. The thermal expansion coefficients of both glasses are lower than the mullite ceramic tiles. The bending strength of the composites after sintering at 1150°C was obviously improved by 10.7% to 106.2 MPa, compared with the mullite ceramic tiles.展开更多
A series of glass sealants for solid oxide fuel cell (SOFC) with compositions SrO (x wt %) La2O3 (15 wt %) Al2O3 (15 wt %) B2O3 (40-x wt %) SiO2 (30 wt %) [x = 10, 15, 20, 25 & 30] [SLABS] have been investigated b...A series of glass sealants for solid oxide fuel cell (SOFC) with compositions SrO (x wt %) La2O3 (15 wt %) Al2O3 (15 wt %) B2O3 (40-x wt %) SiO2 (30 wt %) [x = 10, 15, 20, 25 & 30] [SLABS] have been investigated by quantitative Fourier Transform Infrared Spectroscopy (FTIR). Structural findings from FTIR reveal that with increasing substitu-tion of B2O3 by SrO, even though the B2O3/SiO2 ratio decreases, however the Si-O- non-bridging bond content in the matrix is increasing and glass structure is getting more inverted. UV-Vis Diffused Reflectance Spectroscopy (UV-Vis-DRS) of the glass series shows that electrical band gap of glasses decreases in the series from 3.07eV to 2.97eV with increasing substitution from x = 10 to x = 30. Conductivities of the glass samples were measured by AC impedance spectroscopy and found to be increasing from 2.74 × 10-5 Scm-1 to 1.09 × 10-4 Scm-1 with increasing substitution from x =10 to x = 30.展开更多
Several mineralogical and petrological issues in the field of materials are discussed. These include:the factors affecting the morphology of xonotlite collectives and individual crystals;the application of entringite ...Several mineralogical and petrological issues in the field of materials are discussed. These include:the factors affecting the morphology of xonotlite collectives and individual crystals;the application of entringite mineralogy and properties in the gelled materials;the mineralogical and petrological problems encountered in the study of anorthite bound mullite thermal insulation firebricks. The results show that there is a great space between materials sciences and mineralogy for the applied mineralogists and applied petrologists to explore.展开更多
文摘In order to improve the bending strength of mullite ceramic thin tiles, SiO2-ZnO-Na2O-Y2O3 glass was prepared on the surface of the tiles. The influences of the thermal properties and thermal expansion coefficient of the glass and the sintering temperature on the structure and the property of the composites were investigated by differential thermal analysis (DTA), X-Ray Diffraction (XRD), Raman and scanning electron microscopy (SEM). The bending strength of the composites was measured with an universal testing machine. Results show that the crystallization temperature of the SiO2-ZnO-Na2O-Y2O3 glass is higher than that of SiO2-ZnO-Na2O glass. The corresponding crystallites show more complex structure for the SiO2-ZnO-Na2O-Y2O3 glass. The thermal expansion coefficients of both glasses are lower than the mullite ceramic tiles. The bending strength of the composites after sintering at 1150°C was obviously improved by 10.7% to 106.2 MPa, compared with the mullite ceramic tiles.
文摘A series of glass sealants for solid oxide fuel cell (SOFC) with compositions SrO (x wt %) La2O3 (15 wt %) Al2O3 (15 wt %) B2O3 (40-x wt %) SiO2 (30 wt %) [x = 10, 15, 20, 25 & 30] [SLABS] have been investigated by quantitative Fourier Transform Infrared Spectroscopy (FTIR). Structural findings from FTIR reveal that with increasing substitu-tion of B2O3 by SrO, even though the B2O3/SiO2 ratio decreases, however the Si-O- non-bridging bond content in the matrix is increasing and glass structure is getting more inverted. UV-Vis Diffused Reflectance Spectroscopy (UV-Vis-DRS) of the glass series shows that electrical band gap of glasses decreases in the series from 3.07eV to 2.97eV with increasing substitution from x = 10 to x = 30. Conductivities of the glass samples were measured by AC impedance spectroscopy and found to be increasing from 2.74 × 10-5 Scm-1 to 1.09 × 10-4 Scm-1 with increasing substitution from x =10 to x = 30.
文摘Several mineralogical and petrological issues in the field of materials are discussed. These include:the factors affecting the morphology of xonotlite collectives and individual crystals;the application of entringite mineralogy and properties in the gelled materials;the mineralogical and petrological problems encountered in the study of anorthite bound mullite thermal insulation firebricks. The results show that there is a great space between materials sciences and mineralogy for the applied mineralogists and applied petrologists to explore.
