Accession Number : ADA332713

Title :   De-sintering, A Phenonmena Concurrent with Densification Within Powder Compacts: A Review

Corporate Author : CALIFORNIA UNIV SANTA BARBARA DEPT OF MATERIALS

Personal Author(s) : Lange, F. F.

PDF Url : ADA332713

Report Date : 1994

Pagination or Media Count : 12

Abstract : A morphological instability characterized by the separation of grain pairs and the disappearance of grain boundaries is a common feature in polycrystalline bodies that are constrained from skrinking during mass transport. This instability, know as de-sintering, occurs during grain coarsening as sequentially observed for thin films with columnar microstructures constrained by a substrate, fibers with a 'bamboo' microstructure constrained by a matrix, and powder matrices within composites. De-sintering is a common phenomena in partially dense, polycrystalline bodies; it occurs concurrently with densification phenomena and is emphasized in composites where the partially dense matrix is constrained from shrinking by a reinforcement network. De-sintering occurs in any lower density region were shrinkage is constrained by the average shrinkage of the body.

Descriptors :   *POWDER METALLURGY, *POLYCRYSTALLINE, FIBERS, MICROSTRUCTURE, COMPOSITE MATERIALS, MORPHOLOGY, THIN FILMS, SUBSTRATES, MASS TRANSFER, LOW DENSITY, INSTABILITY, GRAIN BOUNDARIES, SINTERING, SHRINKAGE.

Subject Categories : Metallurgy and Metallography
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE