کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
7991556 | 1516142 | 2018 | 23 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
The effect of microstructure on piezoelectric properties and temperature stability for MnO doped KNN-based ceramics sintered in different atmospheres
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی مواد
فلزات و آلیاژها
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
Lead-free 0.4% MnO doped 0.955K0.5Na0.5NbO3-0.045Bi0.5Na0.5ZrO3 (Abbreviated as 0.955KNN-0.045BNZ) ceramics were prepared by a conventional solid-state sintering method in both ambient air and reducing atmosphere (H2/N2/H2O, oxygen partial pressure po2 â¯=â¯1â¯Ãâ¯10â10 atm). All samples show a polymorphic phase boundary (PPB) with rhombohedral (R)/tetragonal (T) phase. The R phase fraction of ceramics sintered in reducing atmosphere is higher than that of ceramics sintered in ambient air. The valence state of almost all of the Mn ions are +2 for the ceramics sintered in reducing atmosphere. Mixed valence states (+2, +3, +4) of Mn ions coexist in the 0.4% MnO doped 0.955KNN-0.045BNZ ceramic sintered in air. The formation of dipolar defect (MnNbâ²-Vo·· and MnNbâ³-Vo··) in poled ceramics sintered in air is due to the substitution of Nb5+ ions with Mn3+ ions and Mn4+ ions. The ceramics sintered in air show strong dielectric diffusion behavior under electric field (35â¯kV/cm) due to the existence of (â¼200â¯nm) sub-micrometer domains with high activation energy. Nanoscale domains (â¼90â¯nm) in ceramics sintered in reducing atmosphere is the origin of its high piezoelectric properties.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Alloys and Compounds - Volume 752, 5 July 2018, Pages 206-212
Journal: Journal of Alloys and Compounds - Volume 752, 5 July 2018, Pages 206-212
نویسندگان
Yichao Zhen, Zhenyong Cen, Lingling Chen, Peiyao Zhao, Xiaohui Wang, Longtu Li,