کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1473390 991040 2014 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Relaxor behavior in lead-free Ba(Ti1−xScx/2Nbx/2)O3 ceramics
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Relaxor behavior in lead-free Ba(Ti1−xScx/2Nbx/2)O3 ceramics
چکیده انگلیسی

Solid solutions of (1−x)BaTiO3-xBaSc1/2Nb1/2O3 (BT-BSN) with x = 0.025, 0.05, 0.075, 0.1 and 0.125 were prepared by a high temperature solid-state reaction technique. The effects of the Ba(Sc1/2Nb1/2)O3 addition on the phase composition, dielectric properties, as well as polarization-electric field (P-E) loops of the BT-BSN solid solution were investigated. The room-temperature X-ray diffraction analyses of all the ceramics revealed a perovskite phase after sintering at 1350 °C with a composition-dependent symmetry. Temperature and frequency dependence of the dielectric permittivity and losses have been explored: ceramics of compositions x ≤ 0.075 showed normal ferroelectric behavior, while ceramics with x ≥ 0.1 were of relaxor type. The degree of diffuseness and the relaxor effect increase while the transition temperature (TC or Tm) decreases when both scandium and niobium are introduced in the BaTiO3 lattice. Ceramics of composition x = 0.125 exhibited interesting relaxor characteristics at 10 kHz: ΔTm = 20 K, ɛr = 12,000, and Tm = 140 K. In addition, modeled using Vogel–Fülcher relation, this same composition showed the fitting parameters: Ea = 0.0503 eV, f0 = 1.129 × 1014 Hz and TVF = 166.85 K.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Asian Ceramic Societies - Volume 2, Issue 2, June 2014, Pages 132–137
نویسندگان
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