Abstract
New lead-free relaxors have been produced from the K0.5Na0.5NbO3–SrTiO3 (KNN-STO) system. The solid solubility within the studied range of compositions (1 -x) K0.5Na0.5NbO3–xSrTiO3 was observed for x up to 0.33. A pseudo-cubic perovskite structure was determined for x = 0.15 to 0.25. The high density and the uniform distribution of fine grains and pores were confirmed by the translucency of these ceramics. The 0.85KNN-0.15STO composition reaches the dielectric permittivity of above 3000 at room temperature. Dielectric spectroscopy measurements revealed that, as with lead-based complex perovskites, the cationic distribution disorder is reflected in relaxorlike properties, thus suggesting possible applications based on this environmentally friendly lead-free ceramic system.
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Kosec, M., Bobnar, V., Hrovat, M. et al. New lead-free relaxors based on the K0.5Na0.5NbO3–SrTiO3 solid solution. Journal of Materials Research 19, 1849–1854 (2004). https://doi.org/10.1557/JMR.2004.0229
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DOI: https://doi.org/10.1557/JMR.2004.0229