【摘 要】
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Plate-like NaNbO3 particles were used as templates to fabricate grain-oriented 0.96(0.8Na0.5Bi0.5TiO3-0.2 K0.5Bi0.5TiO3)-0.04NaNbO3 (NKBT)ceramics.The effects of the sintering temperature and the soak
【机 构】
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State Key Laboratory of Solidification Processing, College of Material Science and Engineering, Nort
论文部分内容阅读
Plate-like NaNbO3 particles were used as templates to fabricate grain-oriented 0.96(0.8Na0.5Bi0.5TiO3-0.2 K0.5Bi0.5TiO3)-0.04NaNbO3 (NKBT)ceramics.The effects of the sintering temperature and the soaking time on the grain orientation and the microstructure of the textured NKBT ceramics were investigated, and the dielectric relaxor behavior is discussed.The results show that textured ceramics were successfully obtained with orienta tion factor more than 0.8.The textured ceramics have a microstructure with strip-like grains aligning in the direction parallel to the casting plane.The degree of grain orientation increases initially, then decreases with increasing sintering temperature, and increases continuously with increasing soak ing time.The textured NKBT ceramics shows obvious dielectric relaxor characteristics which can be well explained by microdomain-macrodomain transition theory with calculating criterion K.The results show that formation of texture is beneficial to microdomain-macrodomain transition, which lead to weaken relaxor behavior and raise the dielectric constant at T(tr).
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