Tests and modeling for sintering theory
Powder fabrication, sintering studies and computer calculations are discussed in this report. Fine alumina powders were fabricated by instantaneous isothermal dehydration. The sintering of these precipitated alumina powders was studied both isothermally and with a constant heating rate dilatometer. The initial observations on densification were interpreted as Coble creep, which is evidence for a dislocation mechanism in the sintering. Data supporting this mechanism have included grain size by x-ray diffraction, shrinkage using dilatometry, bulk density measurements and specific surface area using gas adsorption. The compacts were also examined in the electron microscope. The phase transformation of gamma to alpha alumina influences the rate of densification. The kinetic analysis indicates a dislocation-aided diffusion process. The sintering of mixed phase (alpha plus gamma alumina) powders also supports the influence of plastic flow.
- Research Organization:
- Rensselaer Polytechnic Inst., Troy, NY (USA). Dept. of Materials Engineering
- DOE Contract Number:
- AC02-82ER12069
- OSTI ID:
- 6678162
- Report Number(s):
- DOE/ER/12069-T2; ON: DE84015110
- Country of Publication:
- United States
- Language:
- English
Similar Records
Sintering stress and microstructure in ceramic powder compacts
Sintering behavior of nanocrystalline {gamma}-Ni-Fe powders
Related Subjects
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
COHERENT SCATTERING
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DENSITY
DIFFRACTION
DISLOCATIONS
FABRICATION
GRAIN SIZE
LINE DEFECTS
MICROSTRUCTURE
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
POWDERS
SCATTERING
SINTERING
SIZE
SURFACE AREA
SURFACE PROPERTIES
X-RAY DIFFRACTION