Localized Densification during the Compaction of Alumina Granules: The Stage I—II Transition |
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Authors: | Consuelo Margarita Kong John J Lannutti |
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Affiliation: | Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210 |
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Abstract: | Tungsten marker layers and X-ray computed tomography were used to monitor the compaction of spray-dried alumina. Local density changes and compaction curves show that the well-known Stage I—II transition indicates an alteration in the direction of transmitted pressure through the uppermost layer. Stage I pressure is dispersed in local agglomerate contacts until "pockets" of low density are eliminated. In Stage II, these deformed/fragmented agglomerates behave as a continuous body and interact with wall friction to transmit pressure nonuniformly into the bulk. Discrete element simulations reproduced the compaction curves and provided clear explanation of the density distribution development. |
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Keywords: | densification alumina compacts/compaction |
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