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Microscopic and macroscopic compaction of cohesive powders

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 نشر من قبل Kevin R. Johnson
 تاريخ النشر 2005
  مجال البحث فيزياء
والبحث باللغة English
 تأليف M. Morgeneyer




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A novel method to investigate the compaction behaviour of cohesive powders is presented. As a sample, a highly porous agglomerate formed by random ballistic deposition (RBD) of micron sized spherical particles is used. A nanomanipulator deforms this small structure under scanning electron microscope observation, allowing for the tracking of individual particle motion. Defined forces are applied and the resulting deformations are measured. The hereby obtained results are compared to results from threedimensional discrete element simulations as well as macroscopic compaction experiments. Relevant simulation parameters are determined by colloidal probe measurements.



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