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Nickel ferrite powder was synthesiszed at temperatures at
lower than350℃ by tartrates method. The particle size of
starting gels can be reducedby grinding therefore, thermal
decomposition of the gels was enhanced, resultin the low-
temperature formation of nickel ferrite powder. The particle
size of synthesized nickel ferrite was investigated using SEM,
the primary particles were found distributed in the range 30 -
60 nm. During the thermal decomposition of the organic
starting gels, γ-Fe2O3transformed to be α-Fe2O3 caused the
abrupt decrease in specific surface area,and the sinterability
of the powder was deteriorated. However, the formation ofα-Fe2
O3 can retarded by the grinding of the starting gels. It is
obvious that, grinding of the starting has influence on the
sinterability of nickel ferrite powders. The starting gels
without grinding which was calcinedat 350℃ can be sintered to
95％ theoretic density at 1250℃ for 4h. When the starting gels
were ground and calcined at 300℃, the nickel ferrite powder can
be sintered to 95％ at 1200℃ for 4h.
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