Microwave sintered silicon nitride ceramics
Silicon nitride-based materials are processed using a variety of thermal heating techniques and procedures, such as sintering, reaction-bonding, and annealing. For sintering, typical silicon nitride processing starts with high {alpha}-phase Si{sub 3}N{sub 4} powders mixed with sintering aids, such as MgO, Y{sub 2}O{sub 3}, and Al{sub 2}O{sub 3}. After consolidation of the mixtures into a shape, they are heated in a nitrogen atmosphere to temperatures of 1700 to 1900{degrees}C to densify. The sintering temperature is dependent on the type and quantity of sintering additives utilized. Densification of silicon nitride compacts occurs through a number of distinct steps. Microwave heating has the capability for volumetric thermal heating of ceramic materials. Silicon nitride-based materials heat in a microwave field by coupling to the sintering additives or grain boundary phases. Previous studies on microwave processing of silicon nitride have reported improved densification during sintering, accelerated nitridation of silicon, and improved high-temperature mechanical properties with thermal annealing of dense materials. In the present research, microwave-sintered silicon nitride ceramics were examined, and the densification behavior and microstructure development correlated with the mechanical properties.
- Research Organization:
- Oak Ridge National Lab., TN (United States)
- Sponsoring Organization:
- DOE; USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 6077408
- Report Number(s):
- CONF-910908-2; ON: DE92004405
- Country of Publication:
- United States
- Language:
- English
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Comparison of properties of sintered and sintered reaction-bonded silicon nitride fabricated by microwave and conventional heating
Comparison of properties of sintered and sintered reaction-bonded silicon nitride fabricated by microwave and conventional heating
Related Subjects
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360203 -- Ceramics
Cermets
& Refractories-- Mechanical Properties
ELECTROMAGNETIC RADIATION
FABRICATION
FRACTURE PROPERTIES
HEATING
MECHANICAL PROPERTIES
MICROWAVE RADIATION
NITRIDES
NITROGEN COMPOUNDS
PNICTIDES
RADIATION HEATING
RADIATIONS
SILICON COMPOUNDS
SILICON NITRIDES
SINTERING