MSA  Vol.2 No.10 , October 2011
Influence of Sintering Temperature on Densification, Structure and Microstructure of Li and Sb Co-Modified (K,Na)NbO3-Based Ceramics
ABSTRACT
Polycrystalline samples of Lead free (K0.5Na0.5)1-x(Li)x(Sb)x(Nb)1-xO3 ceramics with nominal compositions (x = 0.040 to 0.060) have been prepared by high temperature solid state reaction technique. X-ray diffraction (XRD) pattern shows that the crystal structure transforms from orthorhombic to tetragonal as Li and Sb content increases. Normal sintering process yield compounds with density ~98.2% of the theoretical value. Densification of the Li and Sb co-doped KNN ceramics might be explained by the liquid-phase sintering. This may be attributed to the low melting temperature of Li compounds that appears to promote the formation of a liquid phase during sintering.
KEYWORDS
KNN, Perovskite, XRD, SEM

Cite this paper
nullR. Rani and S. Sharma, "Influence of Sintering Temperature on Densification, Structure and Microstructure of Li and Sb Co-Modified (K,Na)NbO3-Based Ceramics," Materials Sciences and Applications, Vol. 2 No. 10, 2011, pp. 1416-1420. doi: 10.4236/msa.2011.210191.
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