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Journal of Microwave Power
and Electromagnetic Energy (JMPEE) |
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TITLE |
Microwave Sintering of Nanometer and Micrometer Ferrite Powders [PDF] |
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AUTHORS |
J.G.P. Binner, 1999 34 3 131-136 |
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Abstract Two ferrite powders, one
nanometre and one micrometresized, have been processed into small pellets using two
different green forming routes, viz. die pressing and slip casting. Prior to
forming using slip casting the powders were dispersed into water using a
range of surfactants and then wet ground in an attempt to reduce the presence
of agglomerates in the as-received powder. The pellets were subsequently
microwave sintered using a TE102 single mode applicator operating
at 2.45 GHz. The die pressed samples produced from the nanometre-sized powder
displayed microstructures that were increasingly duplex in nature as the
sintering temperature increased. This was believed to arise from the highly
agglomerated nature of the as-received powder. When a wet grinding route was
introduced followed by slip casting to prevent reagglomeration
of the powder, the number of agglomerates was very significantly reduced and
a largely submicron microstructure was achieved. Unfortunately, most of the
slip cast pellets suffered from cracking during the sintering process
indicating the presence of stresses in the green bodies produced
Nevertheless, the results achieved suggest that it is possible to microwave
sinter nanometre powder compacts without suffering major grain growth provided
the initial powder is not agglomerated. Key Words: Ceramics, sintering, manometer powders |
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