Quartz is a mineral comprising Si and O atoms in a continuous SiO 4 tetrahedral framework, with each O atom shared between two tetrahedra, resulting in the overall chemical formula of SiO 2. cm for the SiO 2 with ceramic additives.cm for SiO 2 and decreased to 0.12–0.36 Ω.The average resistivity of the Si was 3 Ω The O content in the Si decreased from 6–9 × 10 17 atoms/cm 3 for SiO 2 to less than ~10 16 for SiO 2–Al 2O 3 and SiO 2–MgO. Amorphous SiO 2 layer formation is due to the replacement of the Si position in SiO 2 by Al 3+ and Ti 4+ impurities, which can break the bonds between Si atoms. After Si came into contact with the SiO 2–ceramics, two types of microstructures were found: those with and those without an amorphous SiO 2 reaction layer at the interface. Cracks formed in the Si and SiO 2–ceramic additive sites because of the difference in the coefficients of thermal expansion among the Si, SiO 2, ceramic additives, and reaction phases. Through X-ray diffraction, scanning electron microscopy, and transmission electron microscopy with energy-dispersive spectrometry, the reaction phases of La 2Si 2O 7, Y 2Si 2O 7, and MgSiO 3 (Mg 2SiO 4) were found in the SiO 2 with 10 wt.% La 2O 3, Y 2O 3, and MgO additives. The amorphous SiO 2 changed to cristobalite SiO 2. In this study, 10 wt.% ceramics-Al 2O 3, La 2O 3, Y 2O 3, MgO, and TiO 2-were employed as additives for amorphous SiO 2 after pressing and annealing at 1300 ☌.
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