Accession Number : ADA277092


Title :   Effect of Surface Forces on the Rheology of Particle-Liquid Systems and the Consolidation of Ceramic Powders


Descriptive Note : Annual rept. 1 Feb 1993-31 Jan 1994


Corporate Author : CALIFORNIA UNIV SANTA BARBARA DEPT OF MATERIALS


Personal Author(s) : Lange, Fred F


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a277092.pdf


Report Date : 31 Jan 1994


Pagination or Media Count : 84


Abstract : More reliable ceramics require improved processing reliability. Heterogeneities bought with powders and those inadvertently introduced during processing as well as non-uniform and undefined phase distributions contribute to unreliable processing. Colloldal power treatments can eliminate many heterogeneities and ensure more uniform phase distributions. To ensure that new heterogenelties are not introduced, colloidally treated powers must be piped, as slurries, directly to a die cavity. Slurry consolidation methods based on particle partitioning, e.g., pressure filtration and centrifugation are emphasized in this review. Interparticle potentials play a dominant role in governing the slurry viscosity, maximum particle packing density and the rheology of the consolidate body. These roles will be reviewed with the objective to understand how damage free bodies can be consolidate from slurries to increase the structural reliability of ceramics and their composite


Descriptors :   *POWDERS , *COMPOSITE MATERIALS , *CERAMIC MATERIALS , *RHEOLOGY , MECHANICAL PROPERTIES , ALUMINUM OXIDES , VISCOSITY , FILTRATION , VAN DER WAALS FORCES , CENTRIFUGAL CASTING , DIE CASTING , PATENTS , COLLOIDS , AMMONIUM COMPOUNDS , PRESSURE , SLURRIES , CRACKING(FRACTURING) , PROCESSING


Subject Categories : Ceramics, Refractories and Glass
      Laminates and Composite Materials


Distribution Statement : APPROVED FOR PUBLIC RELEASE