Accession Number : ADA291302

Title :   Nanocrystalline Processing and Interface Engineering of Si3N4-Based Ceramics.

Descriptive Note : Progress rept. 1 Jul-30 Sep 94,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF CHEMICAL ENGINEERING

Personal Author(s) : Ying, Jackie Y.

PDF Url : ADA291302

Report Date : 30 SEP 1994

Pagination or Media Count : 2

Abstract : During the past three months, our efforts have been devoted to synthesizing nanocrystalline Si3N4 and Y2O3. For nanocrystalline Si3N4, a tubular reactor design has been adopted to produce nanoclusters by inert gas condensation in a forced flux flow. This reactor involves various features that allow us to control the synthesis conditions. Evaporation of Si takes place in a cruible located near one end of the reactor. A gas flow is established through the use of a booster pump to bring the nanoclusters generated quickly out of the hot growth zone to prevent particle agglomeration. The nanometer-sized particles are deposited on a liquid-nitrogen cooled flat plate at the other end of the reactor through thermophoresis. (MM)

Descriptors :   *CRYSTALLIZATION, *CERAMIC MATERIALS, DENSITY, POWDERS, PARTICLE SIZE, GAS DYNAMICS, YTTRIUM OXIDES, SILICON NITRIDES, SINTERING.

Subject Categories : Ceramics, Refractories and Glass
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE