Grain Boundaries in Polycrystalline Alumina
نویسندگان
چکیده
منابع مشابه
Capillarity Vector Reconstruction of the Relative Energies of [0001] Tilt Boundaries in Alumina
We have measured the geometry and crystallography of the grain boundaries that form 124 triple junctions in a specimen of polycrystalline alumina. Each of these triple junctions is comprised of [0001] tilt boundaries which were assumed to be in local thermal equilibrium. By using the capillarity vector reconstruction method, we determined the energies of these boundaries as a function of the ti...
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Single crystals of Al2O3 were reproducibly grown from an MgO-doped polycrystalline precursor. The single crystals were grown through controlled abnormal grain growth at temperatures between 16701 and 19451C. It was observed that CaO impurities segregated to the boundary between the single crystal and the polycrystalline region, and formed a wetting intergranular film. This type of film is requi...
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THE following comments are directed to the sections (2) ‘‘revisit to the grain growth problems in alumina’’ and (3) grain growth without a liquid phase in the article of concern. The purpose of this comment is to challenge the authors’ assertions and refute the following arguments, namely, first that ‘‘MgO can be considered a very effective grain growth promoter in the sintering of alumina,’’ s...
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